Developments in Strategic Ceramic Materials

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ISBN: 978-1-119-21173-0
ISSN: 0196-6219

CONTENTS

Preface

Introduction

Geopolymers and Chemically Bonded Ceramics

Properties of Granite Powder Reinforced Potassium Geopolymer
1. Introduction
2. Experimental Procedure
3. Results and Discussion
4. Conclusion
5. References
Ceramic Felt Reinforced Geopolymer Composites
1. Abstract
2. Introduction
3. Experimental Procedures
4. Results
5. Conclusion
6. Acknowledgements
7. References
Ammonia-Borane Geopolymer (AB-G) Composite
1. Abstract
2. Introduction
3. Experimental
4. Results and Discussion
5. Conclusions
6. Acknowledgements
7. References
Monitoring the Structural Evolution During Geopol YMER Formation by ²⁷Al NMR
1. Abstract
2. Introduction
3. Experimental
4. Results and Discussion
5. Conclusion
6. References
Recycled Geopolymer on New Formulations
1. Abstract
2. I. Introduction
3. II. Experimental
4. III. Results and Discussion
5. IV. Conclusion
6. V. References
Impact of Alkaline Solution and Curing Temperature on Micro-Structure and Mechanical Properties of Alkali-Activated Blast Furnaces LAG
1. Abstract
2. Introduction
3. Experimental Methods
4. Results and Discussion
5. Mechanical properties of synthesized samples
6. Conclusion
7. References
Long-term Development of Mechanical Strengths of Alkali-Activated Metakaolin, Slag, Fly Ash, and Blends
1. Abstract
2. Introduction
3. Experimental Procedures
4. Results & Discussion
5. Summary and Conclusion
6. Acknowledgements
7. References
Preparation of Geopolymer-Type Mortar and “Light-Weight Concrete” From Copper Floatation Waste and Coal Combustion by Products
1. Abstract
2. Introduction
3. Experimental
4. Results and Discussion
5. ConclusionS
6. Acknowledgement
7. References
Portland Cement with Luffa Fibers
1. Abstract
2. Introduction
3. Experimental
4. Results
5. Discussion
6. Conclusion
7. References

Virtual Materials (Computational) Design and Ceramic Genome

Two-phase Nanocrystalline/ Amorphous Simulations of Anisotropic Grain Growth Using Q-State Monte-Carlo
1. Abstract
2. Introduction
3. The Model
4. Results
5. ConclusionS
6. Acknowledgments
7. References
First Principles Calculations of Dopant Effects in Boron Subox IDE
1. Abstract
2. Introduction
3. Computational Method
4. Results and Discussion
5. Conclusions
6. Acknowledgements
7. References
Composition Dependent Hardness of Covalent Solid Solutions and its Electronic Structure Origin
1. Abstract
2. Introduction
3. Method and Calculation Details
4. Results and Discussion
5. Conclusion
6. Acknowledgement
7. References
Experimental and Numerical Determination of the Elastic Moduli of Freeze Cast MMC With Different Lamellae Orientation
1. Abstract
2. Introduction
3. Materials and Experimental
4. Material Modelling
5. Results and Discussion
6. Conclusions and Outlook
7. Acknowledgement
8. References
Doping of CeO₂ as a Tunable Buffer Layer for Coated Super Conductors: A DFT Study of Mechanical and Electronic Properties
1. Abstract
2. Introduction
3. Computational Methods
4. Results and Discussion Tetravalent Dopants
5. Conclusions
6. Acknowledgements
7. References and Footnotes
Quantitative Analysis of (La_0.8Sr₀.₂)₀.₉₈MnO_3±δ Electronic Conductivity using Calphad Approach
1. Abstract
2. Introduction
3. Previous Experimental Data
4. Previous Defect Chemistry and Conductivity Analysis
5. Thermodynamic Modeling
6. Results and Discussion
7. Electrical Conductivity Model
8. Acknowledgment
9. References

Advanced Ceramic Coatings

The Effects of Ni₃Al Binder Content on the Electrochemical Response of TiC-Ni₃Al Cermets
1. Abstract
2. Introduction
3. Material and Methods
4. Results and Discussion
5. Conclusions
6. Acknowledgements
7. References
A Study of a βNiAl Bondcoat Deposited onto CMSX-4 Superalloy for Thermal Barrier Applications
1. Abstract
2. Introduction
3. Experimental
4. Results
5. Discussion
6. Conclusions
7. Acknowledgments
8. References
Mechanical Properties of Air Plasma Sprayed Environmental Barrier Coating (EBC) Systems: Preliminary Assessments
1. Abstract
2. 1. Introduction
3. 2. Experimental
4. 3. Results
5. 4. Discussion
6. 4.3 Mixed-Mode Interface Toughness
7. 5. Conclusions
8. 6. Acknowledgements
9. References
Iron-Copper Nitride Thin Films Fabricated by Sputtering
1. Abstract
2. Introduction
3. Experimental Details
4. Results and Observations
5. Conclusions and DiscussionS
6. Acknowledgment
7. References

Materials for Extreme Environments: Ultrahigh Temperature Ceramics and Nanolaminated Ternary Carbides and Nitrides

Influence of Nitrogen Pressure on SHS Synthesis of Ti₂AlN Powders
1. Abstract
2. Introduction
3. Preparation
4. Results and Discussion
5. Conclusion
6. Acknowledgments
7. References
Ultra High Temperature Ceramic Coatings for Environmental Protection of C_f/SiC Composites
1. Abstract
2. Introduction
3. Experimental
4. Results and Discussion
5. Conclusion
6. References

Materials Diagnostics and Structural Health Monitoring of Ceramic Components and Systems

Nanomonitoring of Ceramic Surface
1. Abstract
2. Introduction
3. Experimental
4. Results and Discussion
5. Conclusion
6. Acknowledgement
7. References
Semi-Automated Inspection Unit for Ceramics
1. Abstract
2. Introduction
3. Theory
4. Automated Optical Coherence Tomography
5. OCT for Ceramics Inspection
6. Conclusion
7. References

Advanced Materials and Innovative Processing for the Industrial Root Technology

Modelling of Fluid Flow in Tape Casting of Thin Ceramics: Analytical Approaches and Numerical Investigations
1. Abstract
2. Introduction
3. Modelling Approaches
4. Rheological Behavior
5. Analytical Models
6. Numerical Models
7. Conclusions
8. Future Outlook
9. Acknowledgment
10. References

2nd European-USA Engineering Ceramics Summit and 4th Global Young Investigators Forum

Wettability and Reactivity of Y₂O₃ with Liquid Nickel and its Alloys
1. Abstract
2. Introduction
3. Experimental
4. Results and Discussion
5. Summary
6. Acknowledgements
7. References
Computational Materials Science: Where Theory Meets Experiments
1. Abstract
2. Computational Materials Science: Third Legg of a Tripod
3. Direct Comparison in Three Examples
4. Conclusions
5. Acknowledgements
6. Appendix : Computational Methods
7. References and Footnotes

Author Index

EULA

List of Tables

Properties of Granite Powder Reinforced Potassium Geopolymer

Table I
Table II
Table III

Ceramic Felt Reinforced Geopolymer Composites

Table I
Table II

Monitoring the Structural Evolution During Geopol YMER Formation by ²⁷Al NMR

Table I
Table II

Recycled Geopolymer on New Formulations

Table 1
Table 2

Impact of Alkaline Solution and Curing Temperature on Micro-Structure and Mechanical Properties of Alkali-Activated Blast Furnaces LAG

Table 1
Table 2
Table 3

Long-term Development of Mechanical Strengths of Alkali-Activated Metakaolin, Slag, Fly Ash, and Blends

Table 1.
Table 2.
Table 3.
Table 4.

Preparation of Geopolymer-Type Mortar and “Light-Weight Concrete” From Copper Floatation Waste and Coal Combustion by Products

Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.

First Principles Calculations of Dopant Effects in Boron Subox IDE

Table I.
Table II.

Experimental and Numerical Determination of the Elastic Moduli of Freeze Cast MMC With Different Lamellae Orientation

Table 1.
Table 2.
Table 3.
Table 4.

Doping of CeO₂ as a Tunable Buffer Layer for Coated Super Conductors: A DFT Study of Mechanical and Electronic Properties

Table 1:
Table 2:
Table 3:
Table 4:

The Effects of Ni₃Al Binder Content on the Electrochemical Response of TiC-Ni₃Al Cermets

Table 1
Table 2

A Study of a βNiAl Bondcoat Deposited onto CMSX-4 Superalloy for Thermal Barrier Applications

Table I
Table II

Mechanical Properties of Air Plasma Sprayed Environmental Barrier Coating (EBC) Systems: Preliminary Assessments

Table 1
Table 2
Table 3

Iron-Copper Nitride Thin Films Fabricated by Sputtering

Table I
Table II
Table III
Table IV

Influence of Nitrogen Pressure on SHS Synthesis of Ti₂AlN Powders

Table I

Nanomonitoring of Ceramic Surface

Table 1

Wettability and Reactivity of Y₂O₃ with Liquid Nickel and its Alloys

Table 1

List of Illustrations

Properties of Granite Powder Reinforced Potassium Geopolymer

Fig 1. Scanning electron microscopy image of as-received granite powder examined under accelerating voltage of 20 kV in high vacuum mode
Fig 2. Fracture surface of a coarse granite powder reinforced sample. Inclusions on the millimeter scale, such as this one, might have contributed to lower strengths in the coarse powder samples
Fig 3. Average maximum stress obtained by four point flexure testing in both coarse and fine powder samples. Variation in sample data decreased with increased solids loading, and fine powder significantly increased the flexure strength compared to coarse powder.
Fig 4. Flexural strength measured for coarse powder reinforced samples exposed to various temperatures.
Fig. 5. Shrinkage in the thickness and width of coarse powder reinforced samples. Thickne ss shrank more due to the positioning of the mold during curing which led to particles settling along the thickness.

Ceramic Felt Reinforced Geopolymer Composites

Fig. 1 As-received fiberglass felt from Menards Inc., IL
Fig. 2 As-received basalt felt from Advanced-Filament Technologies
Fig. 3. Basalt-reinforced potassium geopolymer panel of dimensions 8''x6''
Fig. 4. Cut fiberglass-reinforced potassium geopolymer panel of dimensions 8''x6''
Fig. 5. Fiberglass felt-reinforced geopolymer sample broken in 3 point bend testing.
Fig. 6. Basalt felt-reinforced geopolymer sample broken in 3 point bend testing.
Fig. 7. Typical stress strain curve for basalt reinforced geopolymer composite broken in 3 point bend testing.
Fig. 8. Typical stress strain curve for fiberglass reinforced geopolymer composite broken in 3 point bend testing.
Fig. 9. Typical stress strain curve of basalt felt-reinforced geopolymer composite tested in tension.
Fig. 10. Typical stress strain curve of fiberglass felt-reinforced geopolymer composite tested in tension.
Fig. 11. The top sample is of fiberglass felt-reinforced geopolymer composite broken in tension which failed gracefully under shear. The bottom sample is of basalt felt-reinforced geopolymer composite broken in tension which failed in a brittle manner under shear.
Fig. 12. SEM of a basalt felt-reinforced geopolymer composite.
Fig. 13. SEM of a fiberglass reinforced geopolymer composite.
Fig. 14. XRD pattern of metakaolinclay. The amorphous hump is centered on 23 degrees 2Θ with a peak from a titania impurity at 26 degrees 2Θ.
Fig. 15. XRD pattern of basalt felt-reinforced geopolymer composite. The amorphous hump is centered on 28 degrees 2Θ with a peak from a titania impurity at 26 degrees 2Θ.
Fig. 16. XRD pattern of fiberglass felt-reinforced geopolymer composite. The amorphous hump is centered on 28 degrees 2Θ with a peak from a titania impurity at 26 degrees 2Θ.

Ammonia-Borane Geopolymer (AB-G) Composite

Fig. 1 XRD pattern of AB and AB re-crystallized in the geopolymer (AB-G1, AB-G, shifted by 500 and 1000 counts, respectively, AB divided by 3.5). Inset zoomed for 22° to 27°2Theta showing the two strongest peaks. S denotes some peaks related to sodalite, * due to sample holder.
Fig. 2 XRD pattern of metakaolin (MK) and geopolymer cements (aged 4 days) prepared with different MK/KWG ratios by weight (KWG = potassium waterglass). Sharp peaks are related to crystalline impurities unaffected by geopolymerisation.
Fig. 3 Infrared absorption spectra of a geopolymer cement of MK/KWG 35/65%, aged 4 days, and of AB, AB-G₁ and the difference spectrum (Delta) of AB-G₁-AB. N-B, B-H and [BH₄]⁻denote peak positions or ranges of certain vibrations.
Fig. 4 SEM pictures of AB-G₂ (left) and AB (right).
Fig. 5 Experimental determined hydrogen release as a function of used sample mass for AB, AB- G₁ and NaBH₄ with regression lines.
Fig. 6 Infrared absorption spectra of AB, AB-G₂ and filtrates of AB and AB-G₂ after ACHR (acid catalyzed hydrogen release) using 3% HCl solution. Spectra of NH₄Cl and H₃BO₃ are shown for comparison.
Fig. 7 Infrared absorption spectra of AB-G₂, AB-G₂ plus water and dried for 20 h and the same for AB.
Fig. 8 Results of thermogravimetric analysis (TG), a.) and differencial thermo analysis (DTA) b.) of AB-G₂ (solid line) and AB (dashed). Inset in a.) shows TG results of Frueh et al. [22].
Fig. 9 Infrared absorption spectra of AB, AB-G₂ and of samples obtained after the TG/DTA experiments.

Monitoring the Structural Evolution During Geopol YMER Formation by ²⁷Al NMR

Figure 1. Example of deconvoluted ²⁷Al spectrum of S1M2 sample at t=2h(The blue line represents the experimental spectra, and the red line shows the fitted curve).
Figure 2. Recorded ²⁷Al NMR spectra in static mode at (a) 0, (b) 2, (c) 6 and (d) 24 hours of formation for the studied samples.
Figure 3. Evolution of (A) (---) the Al (IV) rate (Al (IV)ti- A (IV)_t0) / Al (IV)_t0) and (B) (...) the A1 (VI) rate (A (VI)ti- A (VI)_t0)/ A (VI)_t0) for (a) () S1 M1, (b) () S1M2, (c) (•) S3M1 and (d) () S3M2 mixtures in function of time.
Figure 4. Evolution of (A) (...) the of Al (IV) reactivity rate (Al(IV)_mixture- Al(IV)_metakaolin)and (B) (---) the Al (VI+V) reactivity rate (Al(VI)_mixture- A(VI+V)_metakaolin) for (a) () S1M1, (b) () S1M2, (c) (•) S3M1 and (d) () S3M2 mixtures in function of time.
Figure 5. Evolution of the Q² position peak versus the time for () S1 M1, () S1M2, (•) S3M1 and () S3M2 samples.
Figure 6. The value of (—) Q² band shift and (---) compressive strengths (7 days) versus the percentage of formed Al (IV) (24 hours) for () S1M1, () S1M2, (•) S3M1 and () S3M2 samples.

Recycled Geopolymer on New Formulations

Figure 1. Synthesis protocol of geo-materials
Figure 2. Position of the different compositions () GX and () G^SX on the Si-Al-K/O ternary diagram. (I) hardening material, (II) geopolymer, and (III) sedimented material and (VI) gel. Gao et al [16].
Figure 3. Q² position versus time for () G0, (×) G²⁰, () G^S20 and () G^S40 as well as (*) E⁰ and () E²⁰. Essaidi et al. [19]
Figure 4. Variation of compressive strength versus strain for G^X reactive (-) G⁰, (-) G^20, (---) G^S20 and (---) G^S40 samples.
Figure 5. SEM micrographs of (a) G0, (b) G²⁰, (c) G^S20 and (d) G^S40 samples.
Figure 6. X-ray patterns of (a) G⁰, (b) G²⁰, (c) G^S20 and (d) G^S40 samples (Quartz, A:anatase
Figure 7. (A) dilatometric curves; (B) the first derivate of the linear shrinkage of (a) G²⁰, (b) G⁰, (c) G^S20 and (d) G^S40.
Figure 8. Evolution of Si ref/Ktot+Al _re _f versus the compressive strength for (O) G⁰, (Δ) G²⁰, () G^S20 and () G^S40 samples and (•) G⁰, () G²⁰, () G^S20 and () G^S40 samples.

Impact of Alkaline Solution and Curing Temperature on Micro-Structure and Mechanical Properties of Alkali-Activated Blast Furnaces LAG

Figure 1. Evolution the pH value of alkaline solution as a function of the M_s modulus for (a) pure solutions and (b) dilute solutions.
Figure 2. (A) Infrared spectra of solutions with a M_s of (a) 1.2, (b) 1.7 and (c) 2.2, and (B) evolution of the ratio (a) Q²/Q⁴, (b) Q²/Q³ and (c) Q²/Q¹ as a function of the M_s modulus.
Figure 3. Evolution of the Q² bands position on infrared spectra (a, d) and of the ratio Q²/Q¹ (c,d) for pure solutions (a, b) and dilute solutions (d, c) respectively.
Figure 4. (A) Infrared spectra and (B) XRD pattern of (a) the initial slag and (b) a synthesized mate rial based on alkali activation of slag.
Figure 5. Thermal analysis of slag and consolidated samples (CS) aged at 20°C or 38° C.
Figure 6. Evolution of the various weight loss (WL₁ (e and f), WL₂ (a and b) and WL₃ (d and c) as a function of the M_s modulus and of the conditions of synthesis (20°C (straight line) or 38°C (dotted line)).
Figure 7. Impact of curing temperature on mechanical properties as a function of time for sample (a) ₂₀CMS₄ and (b) ₃₈CMS₄.
Figure 8. Impact of silicate solution dilution on mechanical properties as a function of time for samples (a) ₃₈CMS₄, (b) ₃₈CMS₅’, (c) ₃₈CMS₆’ and (d) ₃₈CMS₇’.

Long-term Development of Mechanical Strengths of Alkali-Activated Metakaolin, Slag, Fly Ash, and Blends

Figure 2. Development of compressive strength with time for all series of alkali-activated cement mortars (a) alkaline activator of K0.5 series, and (b) alkaline activator of K0.64 series.
Figure 3. Flexural strength as a function of compressive strength. Open square symbols for H-rich mortars
Figure 4. Powder X-ray diffractograms of AAMK cements with time: (a) MK-raw and MK-K0.5 series, (b) Difference pattern (AAMK - x*MK). The s harp diffraction peak at about 25.8°2Theta is related to anatase as typical impurity in the present MK.
Figure 5. Powder X-ray diffractograms of alkali-activated cements with time: (a) H-raw, H and H/MK-K0.5 series. (b) CSH-Tobermorite (Tob) precursor phase. Quartz (Qz), Calcite (Cc) and Tob peak positions as indicated.
Figure 6. ²⁹Si MAS NMR spectra of alkali - activated MK, H and blended cements at 2,000 + days. Thin lines mark some values of chemical shifts for better comparison.

Preparation of Geopolymer-Type Mortar and “Light-Weight Concrete” From Copper Floatation Waste and Coal Combustion by Products

Figure 1. Floatation waste of the Erdenet copper ore dressing factory (a), the filled pond ash of the 3^rd thermal power station (b) and Darkhan city TPS ash pond (c).
Figure 2. XRD patterns of the fly ash and pond ashes.
Figure 3. Compressive strength change of mortars with sand content
Fig.4 SEM micrograph of the fracture surface of mortar
Figure 5. Visible light micrograph of the lightweight concrete

Portland Cement with Luffa Fibers

Fig. 1.(a) Short fiber samples for pH tests, and (b) pH tests.
Fig. 2. SEM images of untreated luffa fibers.
Fig. 3. OM images of luffa fibers untreated and treated with NaOH and HClO.
Fig. 4. Samples fabricated with short fibers cut with a blender, where C: cement; C+unt-fib: cement with untreated fibers, C+fib _NaOH.
Fig. 5. Samples fabricated with short fibers cut with a blender, where C: cement; C+unt-fib: cement with untreated fibers, C+fib _NaOH.
Fig. 6. SEM images for the cement-luffa fibers composite.
Fig. 7. Three point bending strength for the cement-matrix composite fabricated. C: cement (0 wt% fiber), C+fib (unt): cement with untreated fibers, C+fib (HPc): cement with fibers treated with HClO acid, and C+fib (NaOH): cement with fibers treated with NaOH.
Fig. 8. TGA results for untreated, NaOH at 4 wt% and HClO at 4 wt% treated fibers.

Two-phase Nanocrystalline/ Amorphous Simulations of Anisotropic Grain Growth Using Q-State Monte-Carlo

Figure 1. Illustrations of the two events simulated in this study: reorientation and site exchange. Grey and white regions signify the two different phases while the numbered hexagonal elements signify grain orientation.
Figure 2. Hexagonal grain elements and definition of orientation angle (φ).
Figure 3. Elliptical (n=2) Wulff plot with surface energy determination.
Figure 4. Lattice independent results, showing the convergence of average grain area for a resolution of N = 500. (Isothermal; isotropic; Q = 6 0 ; t = 1000 MCS)
Figure 5. The slope of a straight fit through a plot of log (R) vs. log (t) by least squares fitting provides an estimate for the inverse grain growth exponent (1/r). As shown, to a good approximation, the slope (0.49) is in agreement with the power law prediction. (Isothermal; isotropic; Q = 60; t = 100 MCS; N = 500)
Figure 6. Contours of isotropic grain growth evolution. (Q = 6 0 ; t = 500 MCS). The secondary amorphous phase migrates toward grain boundaries and the “pinning” effect resulting in smaller grains with increasing second phase addition.
Figure 7. Contours of anisotropic grain growth evolution. (Q = 60; t = 500 MCS). Like the isotropic system, the second phase continues to migrate to the grain boundaries. It is also observed, that with increased secondary phase the grains tend to become more isotropic in shape.
Figure 8. Average grain area <A> versus time (MCS) for isotropic single and dual phase grain growth. Shows the effect of pinning: Higher the fraction of secondary (B) phase the smaller the average grain size. (J1A = J2A = 1.6 kT; J1AB = J2AB = 0.1 kT)
Figure 9. Average grain area <A> vs. MCS for anisotropic single and dual phase grain growth. (J1A = 1.6 kT, J2A = 0.8 kT; J1AB = J2AB = 0.1 kT)
Figure 10. Average grain area <A> vs. % concentration of secondary phase (B) for isotropic and anisotropic cases. Results show the “Pinning Threshold” corresponding to the minimum allowable secondary phase concentration for fully constrained grain growth. The inset plot shows that a characteristic power-law curve for secondary concentrations less than the “pinning threshold”.

First Principles Calculations of Dopant Effects in Boron Subox IDE

Figure 1. Crystal structure of pristine 2x2x1 B₆O unit cell. B and O atoms are pink and red respectively. Top left- Off-axis view; Bottom left- view perpendicular to basal plane; Top right- view perpendicular to c-axis; Bottom right- close up of Bicosahedra showing the three unique substitutional sites: Polar B (B_p), equatorial B (B_e), and O chain. Note that the terms polar and equatorial strictly refer to the geometric positions of the atoms in the icosahedra and have no relation to their electronic state.
Figure 2. ELF iso-slices through different atomic planes of pristine B₆O. (A) Slice through atomic plane containing a 2 neighboring O interstitials and their bonded equatorial boron, (B) slice through atomic plane containing three co-planar polar boron, (C) slice corresponding to (A) when carbon replaces the equatorial boron, and (D) slice corresponding to (B) when carbon replaces one of the polar boron. Red indicates areas where ELF = 1, whereas ELF = 0 for the dark blue region. The atoms and bonds that are shown as connected balls and sticks exist in the plane slice, whereas the atoms displayed as lines are exterior. Pink, red, and grey balls represent boron, oxygen, and carbon respectively.

Composition Dependent Hardness of Covalent Solid Solutions and its Electronic Structure Origin

Figure 1. Hardness of (a) TiC_xN_1-x and (b) TiN_1-x as functions of composition x, in comparison with available experi mental data.
Figure 2. Single crystal elastic constants and polycrystalline elastic modulus of (a) TiC_xN_1-x and (b) Ti N_1-x as functions of composition x.
Figure 3. Total density of states of (a) TiC_xN_1-x and (b) TiN_1-x.

Experimental and Numerical Determination of the Elastic Moduli of Freeze Cast MMC With Different Lamellae Orientation

Figure 1. Measured and numerical values for the elastic constant C₂₂, plotted against the direction of the alignment of the lamellae. The models for an ideal laminate, Mori-Tanaka and inverse Mori-Tanaka model use the average value of 42 vol.-% ceramic content. Models using the exact ceramic content of the individual micro-specimens are represented by single data points³.
Figure 2. Freeze cast preform with designated pieces for investigation (dimensions in cm).
Figure 3. Crucible with alumina freeze cast preforms and weights and AlSi12 infiltrating material : a) before infiltration, b) after infiltration.
Figure 4. a) Representative miniature tensile specimen (right) in comparison to the size of a 2 Euro cent coin: b) specimen with colored measuring gauge for optical determination of strain during tensile test.
Figure 5. Experimental setup for the tensile tests with equipment for optical strain measurement.
Figure 6: Representative model creation process for typical microstructure : a) original grayscale micrograph (middle part of the tensile specimen fc5_1_1); b) and c) zoom-in into local structure of the high resolution regular rectangular mesh of the model d) used for ABAQUS calculations of the tensile test (tension along vertical direction in the image). Model d) created after binarizing image a) taking into account the measured ceramic content.
Figure 7. Representative orientation analysis (between 0°=180°=vertical direction and 90°=horizontal - CW) of specimen fc5_5_1.
Figure 8. Orientation analysis of specimen fc5_1_1: a) micrograph; b) quantitative distribution of the lamellae within the measuring gauge of the front and back side.
Figure 9. Orientation analysis of specimen fc5_2_1: a) micrograph; b) quantitative distribution of the lamellae within the measuring gauge of the front and back side.
Figure 10. Orientation analysis of speci men fc5_5_1: a) micrograph; b) quantitative distribution of the lamellae within the measuring gauge of the front and back side.
Figure 11. Measured reinforcing content and residual porosity via Archimedes’ principle.
Figure 12. Young’ s modulus plotted against the reinforcing fraction and models according to the models of Voigt - equations (1) - and Reuss - equation (2) (Ec = 3 4 3 GPa).
Figure 13. Young’s modulus plotted against the orientation angle.
Figure 14. Comparison of the Young’s moduli determined via experiment, analytical model and simulation (upper and lower bounds of the known input parameters of the me tal and ceramic) and deviation between experiment and simulation - lower bound).
Figure 15. S₂₂ stress distribution obtained by FE modelling of the specimen fc5_1_1, loading direction (direction 2) is vertical. Corresponding micrograph and FE model are presented in Fig. 6 a) and b).
Figure 16. Specimen fc5_2_1: a) original micrograph, b) transformed FE model (with 372 x 418 plane strain elements), c) S₂₂ stress distribution in the two phases, loading direction (direction 2) is vertical.
Figure 17. S₂₂ stress distribution in specimen fc5_5_1, loading direction (direction 2) is vertical.

Doping of CeO₂ as a Tunable Buffer Layer for Coated Super Conductors: A DFT Study of Mechanical and Electronic Properties

Figure 1: Ball-and-stick representation of Ce_0.75X_0.25O₂.The position of the oxygen vacancy for systems containing vacancies is indicated.
Figure 2: correlation between the linear thermal expansion coefficient α _l and the inverse of the bulk modulus B₀ and equilibrium volume V₀. The solid line indicates a linear fit. Dopant elements are indicated, and CeO₂ indicates the datapoint of the undoped case.

Quantitative Analysis of (La_0.8Sr₀.₂)₀.₉₈MnO_3±δ Electronic Conductivity using Calphad Approach

Figure 1. Quantitative Brouwer Diagrams of LSM-10 (Left) and LSM-20 (right) at 1000°C including all the species in LSM
Figure 2. Quantitative Brouwer Diagrams of LSM-10 (Left) and LSM-20 (right) at 1000, 1100 and 1200°C for Mn²⁺, Mn³⁺ and Mn⁴⁺at B-site
Figure 3. Electrical-conductivity (σ) experimental and calculation data of strontium-doped (20 at.% LaMnO_3-δ at 1273, 1373, and 1473 K, vs. logP₀₂

The Effects of Ni₃Al Binder Content on the Electrochemical Response of TiC-Ni₃Al Cermets

Figure 1. SEM micrographs of polished TiC samples with varying Ni₃Al binder contents: (a) 10 vol. %, (b) 20 vol. %, (c) 30 vol. %, and (d) 40 vol. %.
Figure 2. The comparative results varying from TiC cermets prepared with 10 vol. % Ni₃Al binder. The definition for the breakdown potential, E_b, is also shown in this figure, where the current density begins to increase again after passivation.
Figure 3. Combined potentiodynamic polarization plots for each of the TiC-based cermets, prepared with 10 to 40 vol. % Ni₃Al binder content.
Figure 4. Post-corrosion testing SEM micrographs of TiC with 10 vol. % Ni₃Al.
Figure 5. Post-corrosion testing SEM micrographs of TiC with 40 vol. % Ni₃Al.
Figure 6. ICP results of solution remaining in flat cell upon completion of corrosion testing.
Figure 7. EDS analysis on remaining Ti, C, Ni and Al within the sample following corrosion testing (compositions in wt. %).

A Study of a βNiAl Bondcoat Deposited onto CMSX-4 Superalloy for Thermal Barrier Applications

Figure 1(a) shows the schematic for the in-situ chemical vapour deposition (CVD), commonly known as pack aluminising and (b) diffusion treatment cycle of coatings.
Figure 2 microstructure, chemical composition and phases of the as-deposited coatings; (a) BC cross-section, (b) the magnified image of (a), (c) their EDS analysis and (d) XRD spectrum.
Figure 3 shows the BC stresses measured in as-deposited condition.
Figure 4 TGA, PLPS and XRD analyses of the BC; (a) TGA at 1150 ^oC for 100 hours, (b) TGO stresses measured at room temperature, (c) TGO phases measured by PLPS and (d) XRD peaks of the oxidized BC surface.
Figure 5 presents the microstructure of BC after oxidation at 1150^oC for 100 hours in air; (a) TGO surface, (b) high magnification BSE image of the TGO surface showing the mixture of the TiO₂ and/or NiAl₂O₄ phases as white spots, identified by EDS analysis, (c) Cr/W/Ta-rich precipitates (also white spots) at the surface of the BC after spallation (d) the typical fracture morphology (equiaxed and columnar) of the TGO.
Figure 6 (a) microstructure of the intact TGO taken at low magnification showing spallation of TGO, (b) magnified TGO surface which shows TiO₂/spinels as white particles and the background is the alumina and (c) presents the degree of spallation vs oxidation time.
Figure 7 shows the cross-sections of oxidized BC; (a) the microstructure of the BC evolved after oxidation at1 150^oC/100 hours. It shows the γ’-Ni₃Al, TGO and βNiAl phases, while (b) is a magnified image of (a) which exhibits these phases more clearly and (c) presents the TCPs that were found mainly below the βNiAl matrix in the substrate after oxidation.
Figure 8a - d shows the cross-sectional EDS analysis of the phases that were evolved after oxidation; (a) βNiAl, (b) γ’-Ni₃Al, (c) precipitates and (d) oxide intrusions at γ’/α-Al₂O₃interface.

Mechanical Properties of Air Plasma Sprayed Environmental Barrier Coating (EBC) Systems: Preliminary Assessments

Figure 1. Photographs of (a) the 13 mm thick air plasma sprayed Yb₂Si₂O₇ stand-alone plate in the deposition fixture, (b) Si test bars after machining from a stand-alone APS silicon plate, and (c) APS Yb₂Si₂O₇ coated Si test bars.
Figure 2. Schematic illustrations of (a) the 4-point bending apparatus used for isothermal flexure tests (toughness, strength, and creep), and (b) the 4-point bending apparatus used for laser thermal gradient creep flexure testing. The incident laser beam had a ~25 mm diameter uniform profile. To create the uniform incident heat flux, a rotated integrator lens was used to distribute the beam. Both fixtures are operated in lab air.
Figure 3. Schematic illustration of the 4-point bending test configuration used for mixed-mode fracture testing. The inset shows the EDM notch used to establish a “T”-shaped pre-crack in the stiffener and APS coating.
Figure 4. BSE mode SEM images of the as-deposited Yb₂Si₂O₇ stand-alone plate at a series of magnifications illustrating features relevant to the mechanical response showing (a) low magnification image with intersplat porosity, (b) the presence of (lighter contrast) Si depleted splats, (c) partially melted HOSP particles bound in the matrix, and (d) isolated intersplat pores and poorly adhered splat boundaries.
Figure 5. Isothermal 4-point flexure creep data of air plasma sprayed Yb₂Si₂O₇. (a) Shows the effect of temperature on the surface strain versus time behavior for a calculated surface stress of 15.8 MPa. (b) The pseudo-strain versus time response during the primary creep regime of the tests shown in (a).
Figure 6. Laser thermal gradient creep curves for APS Yb₂Si₂O₇. (a) Strain and load curves for the two-temperature test with front face, back face, and inverse T average (weighted) test temperatures. (b) Linear fit strain equations for the two different temperature regimes of the thermal gradient creep test.
Figure 7. Determination of creep stress parameter “n” for APS Yb₂Si₂O₇ through optimization of R² in an Arrhenius-type creep activation energy (E_a) determination plot.
Figure 8. BSE SEM images of (a) the as-deposited stand-alone Si plate showing the uniform distribution of pores. (b) Higher magnification image showing intersplat boundary and pore structures. (c) Low magnification image of an APS Yb₂Si₂O₇ coated silicon test specimen used to protect the sample from oxidation during laser thermal gradient testing. (d) Higher magnification image of the Yb₂Si₂O₇ – Si coating interface showing good interface adherence.
Figure 9. Laser thermal gradient creep curves for APS Si. (a) Strain and load curves for the four- temperature test with front face, back face, and Si test temperatures. (b) Linear fit strain equations for the four different temperature regimes of the thermal gradient creep test.
Figure 10. Creep activation energy (E_a) determination for APS Si in an Arrhenius-type plot.
Figure 11. Load and displacement curves for a 4-point bending interfacial toughness test.

Iron-Copper Nitride Thin Films Fabricated by Sputtering

Figure 1. Experimental setup for RF/ DC plasma magnetron sputtering
Figure 2. Iron and copper target used for embedding copper in FeN film
Figure 3. Cross sectional SEM image of sample A
Figure 4. Cross sectional SEM image of sample D
Figure 5. Cross sectional SEM image of sample E
Figure 6. XRD spectrum of sample A
Figure7. XRD spectrum of sample D
Figure 8. X-ray reflectivity curves for sample B
Figure 9. XPS depth profile of the FeN layer of sample A
Figure 10. XPS depth profile of sample B
Figure 11. XPS depth profile of sample C2
Figure 12 XPS depth profile of sample D
Figure 13. Hysteresis loop of sample B
Figure 14. Hysteresis loop of sample C1
Figure 15. Hysteresis loop of sample D
Figure 16. Hysteresis loop of sample E

Influence of Nitrogen Pressure on SHS Synthesis of Ti₂AlN Powders

Figure 1. XRD pattern of the Ti₂AlN powders obtained by SHS reaction 6 under 1.5 N₂ atm.
Figure 2. XRD pattern of the Ti₂AlN powders obtained by SHS reaction 6 under 5 N₂ atm.
Figure 3. Morphology of the Ti₂AlN powders obtained by SHS reaction 6 under 1.5 N₂ atm. (left) and 5N₂ atm. (right).

Ultra High Temperature Ceramic Coatings for Environmental Protection of C_f/SiC Composites

Figure 1: Schematic overview of the Polymer-Infiltration-Pyrolysis process¹² (A) and High Performane Plasma Coating process (B)
Figure 2: Free hot gas jet of the Airbus Group “Environmental Relevant Burner Rig-Kerosene” (ERBURIG^K) test facility¹²
Figure 3: SEM image of fracture front view of ZrB₂ via HPPC on a glass substrate and atomic concentration depth profile via XPS
Figure 4: SEM image of fracture (A) and atomic concentration depth profile via XPS (B) of a ZrB₂ coating, fabricated with 12 s coating time on a C_f/SiC SiCARBON^TM substrate
Figure 5: SEM images of HPPC based ZrB₂ coatings on C_f/SiC SiCARBON^TM substrates with a coating time of 12 s (A), 60 s (B), 90 s (C), 120 s (D)
Figure 6: Coating thickness of HPPC based ZrB₂ coatings on C_f/SiC SiCARBON^TM depending on the coating time
Figure 7: Fracture (A) and surface (B) of a HPPC based ZrB₂ coating with a coating time of 90 s on C_f/SiC SiCARBON^TM substrate
Figure 8: Fracture (A) and surface (B) of a HPPC based 90 wt.-% ZrB₂-10 wt.-% SiC coating with a coating time of 90 s on C_f/SiC SiCARBON^TM substrate
Figure 9: XPS atomic concentration depth profiles of HPPC based ZrB₂ (A) and ZrB₂-SiC (B) coatings on C_f/SiC SiCARBON^TM substrates
Figure 10: Macroscopic morphologies of HPPC based ZrB₂ (A) and ZrB₂-SiC (B) coatings on C_f/SiC SiCARBON^TM after 15 min ERBURIG^K testing at 1800 °C-1900 °C; macroscopic morphology of CVD-SiC coating on C_f/SiC SiCARBON^TM tested at the same conditions for 105 min (C)
Figure 11: Cross-sections of HPPC based ZrB₂ and ZrB₂-SiC coatings on C_f/SiC SiCARBON^TMsubstrate before (A+D) and after ERBURIG^K testing; intermediate region (B+E) and central region (C+F)
Figure 12: XPS atomic concentration depth profiles of HPPC based ZrB₂ (A) and ZrB₂-SiC (B) coatings on C_f/SiC SiCARBON^TM substrates after ERBURIG^K testing for 15 min at 1800- 1900 °C
Figure 13: Surface XRD pattern of HPPC based ZrB₂ (A) and ZrB₂-SiC (B) coatings on C_f/SiC SiCARBON^TM after ERBURIG^K testing for 15 min at 1800-1900 °C

Nanomonitoring of Ceramic Surface

Figure 1. SEM images of supramolecular complexes of (a, b) Eu(BPhen)₂(NO₃)₃ and (c, d) - ND–Eu(BPhen) ₂(NO₃)_2.
Figure 2. Spectra of fluorescence excitation at λ_reg = 613 (a) and fluorescence spectra at λ_ex = 300 nm (6) of powders: 1 -Eu(BPhen)₂(NO₃)₃, 2 - ND-Eu(BPhen)₂(NO₃)_2/
Figure 3. The kinetics of luminescence of crystalline powders at excitation by pulsed xenon lamp through glass light-filters (pulse duration is ~ 2 mks, λ_ex ~350 nm): 1 - Eu(BPhen)₂(NO₃)₃; 2– ND–Eu(BPhen)₂(NO₃)₂.
Figure 4. Photos images of inspected ceramic surfaces: a- all samples and 1, 2, 3 respectively). Irradiation by light of NC4U133A-E diode with λ_max = 365 nm.
Figure 5. Fluorescent microscopy images of ceramic surfaces (λ_ex = 365 nm, λ_reg = 630-660nm).

Semi-Automated Inspection Unit for Ceramics

Figure 1: scheme of OCT-device setup with basic module and 1d applicator; SLD: superluminescent diode, BS: beam splitter, RM: reference mirror, FL: focusing lens
Figure 2: Ongoing compaction of an yttria stabilized zirconia material during sintering from left to right with decreasing pore density and pore sizes; OCT B-Scan
Figure 3: Organic impurity (circle) and visible in-depth artifacts originated from surface markings (square); OCT B-Scan
Figure 4: Cracks in a zirconium oxide;OCT B-Scan
Figure 5: Porous ceramic structure as bone scaffold substitute.

Modelling of Fluid Flow in Tape Casting of Thin Ceramics: Analytical Approaches and Numerical Investigations

Figure 1. Schematic illustration of the tape casting process in 2D.
Figure 2. a- Results of quasi-steady state modelling and their comparison with conventional steady state model as well as experimental data¹⁴, b- impact of increasing the value of the required tape thickness on the height of the slurry behind both doctor blades (H₁ for first and H₂ for the second one) with a sufficient and insufficient belt velocity¹⁵.
Figure 3. Numerical modelling and corresponding experiments values of side flow factor (α) influenced by a- substrate velocity, b- slurry height.²¹ The (dash-) lines are guide to the eye.
Figure 4. a- schematic representation of the interface between the two adjacent layers, b- the change in the predicted interface between the adjacent layers for different cases (i) ρ₂ = 2ρ₁ and μ₂ = μ₁, (ii) ρ₂ = 2ρ₁ and μ₂=μ₁, (iii) case-i with doubled substrate velocity, and (iv) case-ii with doubled substrate velocity.

Figure 5. Distribution of the volume fraction for the particles inside the ceramic slurry, a- without applying, and b- with applying the proposed model by Jabbari et al.³⁷

Figure 6. a- Variation of water content due to evaporation for different tape thickness of δ = 400, 300, 200 μm, b- the results of numerical modelling for the different drying modes for the tape thickness of δ = 400 μm

Wettability and Reactivity of Y₂O₃ with Liquid Nickel and its Alloys

Fig. 1 Testing procedures used in sessile drop (SD) tests: (a-b) contact heating (ch) of a metal/substrate couple; (c-d) drop pushing (dp) and drop displacement at testing temperature from 1^st to 2^nd position

Fig. 2 Wettability kinetics in SD/ch+dp tests (1500°C, 5 min): (a) pure Ni/Y₂O₃; (b) NiCo10/Y₂O₃ Test 1 and Test 2 correspond to the 1^st and 2^nd position of the drop after its displacement

Fig. 3 Wettability kinetics in SD/ch+dp tests (1500°C, 5 min): (a) NiCr10/Y₂O₃; (b) NiW10/Y₂O₃ Test 1 and Test 2 correspond to the 1^st and 2^nd position of the drop after its displacement

Fig. 4 Wettability kinetics in SD/ch tests (1500°C, 5 min): (a) IN740/Y₂O₃; (b) H282/Y₂O₃

Fig. 5 (a) Wettability kinetics in NAl22/Y₂O₃ (SD/ch - 1620°C, 15 min); (b-h) solidified couples with (b) NiAl12, (c) Ni, (d) NCo10, (e) NiCr10, (f) NiW10, (g) IN740, (h) H282; (c-f) SD/ch+dp - 1500°C, 15 min; (g,h) SD/ch - 1500°C, 5 min; 3^rd image in (b,g,h) is the bottom view of disconnected drop

Fig. 6SEM images of Ni/Y₂O₃ (SD/ch+dp): (a) top view; (b) drop surface near TL

Fig. 7 SEM images of NiCo10 /Y₂O₃ (SD/ch+dp): (a) general top view showing 1^st position of the drop with well distinguished area under solid alloy sample before its melting; (b-d) area marked in (a)

Fig. 8 SEM images of NiCr10 /Y₂O₃ (SD/ch+dp): (a) top view showing 1^st position of the drop with well distinguished area under solid alloy sample before its melting; (b-d) areas marked in (a)

Fig. 9 SEM images of NiW10 /Y₂O₃ couple (SD/ch+dp): (a) top view showing 1^st and 2^nd positions of the drop with area under solid alloy sample before its melting; (b-f) area marked in (a)

Fig. 10 SEM+EDS analysis of the substrate surface of NiAl12/Y₂O₃ couple (SD/ch -1620°C, 15min): (a) general view of the surface outside of mother drop near TL showing a few small daughter droplets; (b,c) more detailed structure of the top surface of daughter droplet; (d-f) structure of the substrate under the drop at the fractured surface.

Fig. 11 SEM+EDS analysis in marked area of cross-sectioned couples: (a-b) IN740/Y₂O₃ (SD/ch -1500 °C, 5 min), (c-d) H282/Y₂O₃ (SD/ch - 1500 °C, 5 min)

Fig. 12 SPM analysis (100μm×100μm) of the substrate surface of H282/Y₂O₃ couple: (a) 2D-image of in the TL region, (b) 2D-surface topography recorded along scanline shown in (a)

Computational Materials Science: Where Theory Meets Experiments

Figure 1: Different flavours of materials research.

Figure 2: (left) Ball-and-stick representation of the Pt induced nanowire model. Black/grey spheres indicate the positions of the Pt/Ge atoms. (right) Simulated STM image of the Pt induced nanowire model, showing two nanowires.

Figure 3: Ball -and-stick representation of the cubuc fluorite unit cell (left) and the primitive pyrochlore unit c ell (right). Light grey/dark grey spheres show the positions of the Ce/La atoms, while the O positions are indicated by the black spheres. In case of the pyrochl ore structure also one of the two vacancies is indicated (Vac).

Figure 4: Comparison of the simulated XRD spectra for the pyrochlore (top, shifted by 1%) and defective disordered fluorite (bottom) structures. Prototypical pyrochlore reflections are indicated. Note the intensity scale.

Figure 5: Ball-and-stick representation of the MIL-47(V) MOF (left). Calculated P(V) curves for the ferromagnetic and antiferromagnetic configurations of the MIL-47(V) MOF (right). The equilibrium volume V₀, and transition pressures P_t are indicated.

A Collection of Papers Presented at the 39th International Conference on Advanced Ceramics and Composites January 25-30, 2015 Daytona Beach, Florida

A Collection of Papers Presented at the
39th International Conference on
Advanced Ceramics and Composites
January 25-30, 2015
Daytona Beach, Florida