Ceramic Composite Attachments for Transmission of High-Torque Loads

1994 ◽  
Vol 116 (3) ◽  
pp. 611-615
Author(s):  
J. W. Brockmeyer ◽  
A. C. Straub ◽  
E. J. Krieg
Keyword(s):  
Rocket Engine ◽  
Ceramic Matrix Composites ◽  
Inlet Temperature ◽  
Matrix Composites ◽  
Thermal Expansion Coefficients ◽  
Low Thermal Expansion ◽  
Current Design ◽  
Ground Test ◽  
High Torque ◽  
Improved Performance

The use of fiber-reinforced ceramic matrix composites (FRCMC) for advanced turbopump (T/P) hot-section components offers a number of potential advantages relative to the use of “conventional” materials. Among these advantages are reduced weight, enhanced life with reduced maintenance, and improved performance achievable by increasing the turbine inlet temperature. FRCMC are, however, emerging materials, and their design and analysis present unique challenges. These composites have relatively low thermal expansion coefficients and low strain-to-failure characteristics, and they have nonlinear, anisotropic properties. These characteristics particularly complicate the design of attachments to mating metallic components within a T/P. In an ongoing program, an FRCMC stator and rotor for a rocket engine T/P are being developed for eventual ground test demonstration. The rotor attachment is designed to transmit high-torque loads and provides an example of a design methodology that is compatible with current analytical capabilities. The approach used and described herein applies an empirically derived materials properties data base in combination with macromechanical analysis to reach a solution to this design challenge. This example demonstrates both the capabilities and the limitations of current design and analysis practices and provides direction for future development. A curvic coupling was chosen to meet the specific design goals and will be fabricated and tested to verify the design.

scholarly journals Ceramic Composite Attachments for Transmission of High Torque Loads

1993 ◽  
Author(s):  
Jerry W. Brockmeyer ◽  
Andreas C. Straub ◽  
Eric J. Krieg
Keyword(s):  
Rocket Engine ◽  
Ceramic Matrix Composites ◽  
Inlet Temperature ◽  
Matrix Composites ◽  
Thermal Expansion Coefficients ◽  
Low Thermal Expansion ◽  
Current Design ◽  
Ground Test ◽  
High Torque ◽  
Improved Performance

The use of fiber-reinforced ceramic matrix composites (FRCMC) for advanced turbopump (T/P) hot-section components offers a number of potential advantages relative to the use of ‘conventional’ materials. Among these advantages are reduced weight, enhanced life with reduced maintenance and improved performance achievable by increasing the turbine inlet temperature. FRCMC are, however, emerging materials, and their design and analysis present unique challenges. These composites have relatively low thermal expansion coefficients and low strain-to-failure characteristics, and they have nonlinear, anisotropic properties. These characteristics particularly complicate the design of attachments to mating metallic components within a T/P. In an ongoing program*, an FRCMC stator and rotor for a rocket engine T/P are being developed for eventual ground test demonstration. The rotor attachment is designed to transmit high torque loads and provides an example of a design methodology which is compatible with current analytical capabilities. The approach used and described herein applies an empirically derived materials properties data base in combination with macromechanical analysis to reach a solution to this design challenge. This example demonstrates both the capabilities and the limitations of current design and analysis practices and provides direction for future development. A curvic coupling was chosen to meet the specific design goals and will be fabricated and tested to verify the design.

Ceramic Matrix Composite Applications in Advanced Liquid Fuel Rocket Engine Turbomachinery

1993 ◽  
Vol 115 (1) ◽  
pp. 58-63 ◽  
Author(s):  
J. W. Brockmeyer
Keyword(s):  
Liquid Fuel ◽  
Rocket Engine ◽  
Ceramic Matrix Composite ◽  
Weight Ratio ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
High Heat ◽  
Heat Fluxes ◽  
Inlet Temperature ◽  
Improved Performance

Hot gas path components of current generation, liquid fuel rocket engine turbopumps (T/P) are exposed to severe thermal shock, extremely high heat fluxes, corrosive atmospheres, and erosive flows. These conditions, combined with high operating stresses, are severely degrading to conventional materials. Advanced turbomachinery (T/M) applications will impose harsher demands on the turbine materials. These demands include higher turbine inlet temperature for improved performance and efficiency, lower density for improved thrust-to-weight ratio, and longer life for reduced maintenance of re-usable engines. Conventional materials are not expected to meet these demands, and fiber-reinforced ceramic matrix composites (FRCMC) have been identified as candidate materials for these applications. This paper summarizes rocket engine T/M needs, reviews the properties and capabilities of FRCMC, identifies candidate FRCMC materials and assesses their potential benefits, and summarizes the status of FRCMC component development with respect to advanced liquid fuel rocket engine T/M applications.

Ceramic Matrix Composite Applications in Advanced Liquid Fuel Rocket Engine Turbomachinery

1992 ◽  
Author(s):  
Jerry W. Brockmeyer
Keyword(s):  
Liquid Fuel ◽  
Rocket Engine ◽  
Ceramic Matrix Composite ◽  
Weight Ratio ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
High Heat ◽  
Heat Fluxes ◽  
Inlet Temperature ◽  
Improved Performance

Hot gas path components of current generation, liquid fuel rocket engine turbopumps (T/P) are exposed to severe thermal shock, extremely high heat fluxes, corrosive atmospheres and erosive flows. These conditions, combined with high operating stresses, are severely degradative to conventional materials. Advanced turbomachinery (T/M) applications will impose harsher demands on the turbine materials. These demands include higher turbine inlet temperature for improved performance and efficiency, lighter weight for improved thrust-to-weight ratio, and longer life for reduced maintenance of re-usable engines. Conventional materials are not expected to meet these demands, and fiber-reinforced ceramic matrix composites (FRCMC) have been identified as candidate materials for these applications. This paper summarizes rocket engine T/M needs, reviews the properties and capabilities of FRCMC, identifies candidate FRCMC materials and assesses their potential benefits, and summarizes the status of FRCMC component development with respect to advanced liquid fuel rocket engine T/M applications.

scholarly journals Environmental Barrier Coatings Made by Different Thermal Spray Technologies

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 784 ◽  
Author(s):  
Robert Vaßen ◽  
Emine Bakan ◽  
Caren Gatzen ◽  
Seongwong Kim ◽  
Daniel Emil Mack ◽  
...  
Keyword(s):  
Plasma Spraying ◽  
Thermal Spray ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Atmospheric Plasma ◽  
Matrix Composites ◽  
Barrier Coatings ◽  
Environmental Barrier Coatings ◽  
Environmental Barrier ◽  
Thermal Expansion Coefficients

Environmental barrier coatings (EBCs) are essential to protect ceramic matrix composites against water vapor recession in typical gas turbine environments. Both oxide and non-oxide-based ceramic matrix composites (CMCs) need such coatings as they show only a limited stability. As the thermal expansion coefficients are quite different between the two CMCs, the suitable EBC materials for both applications are different. In the paper examples of EBCs for both types of CMCs are presented. In case of EBCs for oxide-based CMCs, the limited strength of the CMC leads to damage of the surface if standard grit-blasting techniques are used. Only in the case of oxide-based CMCs different processes as laser ablation have been used to optimize the surface topography. Another result for many EBCs for oxide-based CMC is the possibility to deposit them by standard atmospheric plasma spraying (APS) as crystalline coatings. Hence, in case of these coatings only the APS process will be described. For the EBCs for non-oxide CMCs the state-of-the-art materials are rare earth or yttrium silicates. Here the major challenge is to obtain dense and crystalline coatings. While for the Y2SiO5 a promising microstructure could be obtained by a heat-treatment of an APS coating, this was not the case for Yb2Si2O7. Here also other thermal spray processes as high velocity oxygen fuel (HVOF), suspension plasma spraying (SPS), and very low-pressure plasma spraying (VLPPS) are used and the results described mainly with respect to crystallinity and porosity.

Preparation of Bulk Graphene Nanoplatelets by Spark Plasma Sintering — Electrical and Thermal Properties

2016 ◽  
Vol 15 (05n06) ◽  
pp. 1660003 ◽  
Author(s):  
Mattipally Prasad ◽  
Tata N. Rao ◽  
P. S. R. Prasad ◽  
D. Suresh Babu
Keyword(s):  
Spark Plasma Sintering ◽  
Elevated Temperatures ◽  
Extreme Temperature ◽  
Ceramic Matrix Composites ◽  
Lattice Parameter ◽  
Graphene Nanoplatelets ◽  
Matrix Composites ◽  
Thermal Expansion Coefficients ◽  
Plasma Sintering ◽  
Spark Plasma

Consolidation of graphene nanoplatelets (GNPs) by spark plasma sintering (SPS) to study the feasibility of its structure retention at extreme temperature and pressure conditions. Structural characterization of the GNP powder and pellet were carried out by Micro-Raman, SEM, and TEM. HT-XRD. A.C. and D.C. conductivity of GNP pellet is carried out at room temperature. GNPs survived its structure in the SPS processing at an extreme temperature of 1850[Formula: see text]C and uni-axial pressure 60[Formula: see text]MPa, vacuum at [Formula: see text] Torr. Our study shows the potential for GNPs to be successfully used as a reinforcing in ceramic matrix composites using SPS. The diffraction has been accurately calibrated to waterfall the shift in 2[Formula: see text] values at elevated temperatures. The corrected lattice parameter data have been used to estimate the instantaneous and mean thermal expansion coefficients as a function of temperature. The lattice parameters “[Formula: see text]” and “[Formula: see text]” for powder and pellet GNP is found to be 0.2456(1)[Formula: see text]nm and 0.6700(2)[Formula: see text]nm, respectively. The thermal expansivity of GNP powder and pellet along “[Formula: see text]”- and “[Formula: see text]”-axis are found to be [Formula: see text][Formula: see text]K[Formula: see text], [Formula: see text][Formula: see text]K[Formula: see text] and [Formula: see text][Formula: see text]K[Formula: see text], [Formula: see text][Formula: see text]K[Formula: see text], respectively. Electrical conductivity of GNP pellet is found to be 5700[Formula: see text]S/m.

Preparation and Characteristics of ZrO2/ZrW2O8 Composites with Low Thermal Expansion

2018 ◽  
Vol 768 ◽  
pp. 87-91
Author(s):  
Jin Ping Li ◽  
Cheng Yang ◽  
Yu Han Li ◽  
Song He Meng
Keyword(s):  
Thermal Expansion ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Cold Isostatic Pressing ◽  
Raw Material ◽  
Matrix Composites ◽  
Low Thermal Expansion

The ZrO2/ZrW2O8 ceramic matrix composites have been prepared by the two different processes: (1) ZrO2 and ZrW2O8 powders were mixed directly as raw material, then compacted by cold isostatic pressing under 200MPa, and finally, the ceramic matrix composites with low thermal expansion can be prepared by use of heat-pressing sintering or atmospheric sintering at temperature 1215oC. (2) ZrO2 (with excess mass) and WO3 powers were mixed as raw material, then compacted by cold isostatic pressing under 200MPa, and finally, the ZrO2/ZrW2O8 ceramic matrix composites can be made by use of heat-pressing sintering or atmospheric sintering at temperature 1215 oC after ZrW2O8 were synthesized by in-situ reaction of ZrO2 and WO3 powders at the same temperature. The microstructure, density, ZrW2O8 decomposition degree and the thermal expansion coefficient were compared among the sintered samples fabricated by the above two different methods, and affected by the different process parameters. The results show that the ceramic matrix composites with low thermal expansion are really composed of ZrO2, ZrW2O8 and WO3, and their relative densities are all more than 95%. Compared with the composites prepared by in-situ reaction, the densities, ZrW2O8 decomposition degree and the thermal expansion coefficient of the composites made by direct mixing are higher, less and smaller, respectively.

Ceramic Matrix Composites for Rocket Engine Turbine Applications

1993 ◽  
Vol 115 (1) ◽  
pp. 64-69 ◽  
Author(s):  
T. P. Herbell ◽  
A. J. Eckel
Keyword(s):  
Rocket Engine ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Matrix Composites ◽  
Test Results ◽  
Test Rig ◽  
Heating Rates ◽  
Isothermal Exposure ◽  
Monolithic Ceramics ◽  
Exposure Evaluation

A program to establish the potential for introducing fiber-reinforced ceramic matrix composites (FRCMC) in future rocket engine turbopumps was instituted in 1988. A brief summary of the overall program (both contract and in-house research) is presented. Tests at NASA Lewis include thermal upshocks in a hydrogen/oxygen test rig capable of generating heating rates up to 2500°C/s. Post-thermal upshock exposure evaluation includes the measurement of residual strength and failure analysis. Test results for monolithic ceramics and several FRCMCs are presented. Hydrogen compatibility was assessed by isothermal exposure of monolithic ceramics in high-temperature gaseous hydrogen plus water vapor.

scholarly journals Ceramic Matrix Composites for Rocket Engine Turbine Applications

1992 ◽  
Author(s):  
Thomas P. Herbell ◽  
Andrew J. Eckel
Keyword(s):  
Rocket Engine ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Matrix Composites ◽  
Test Results ◽  
Test Rig ◽  
Heating Rates ◽  
Isothermal Exposure ◽  
Monolithic Ceramics ◽  
Exposure Evaluation

A program to establish the potential for introducing fiber reinforced ceramic matrix composites (FRCMC) in future rocket engine turbopumps was instituted in 1987. A brief summary of the overall program (both contract and in-house research) is presented. Tests at NASA Lewis include thermal upshocks in a hydrogen/oxygen test rig capable of generating heating rates up to 2500 °C/sec. Post thermal upshock exposure evaluation includes the measurement of residual strength and failure analysis. Test results for monolithic ceramics and several FRCMC are presented. Hydrogen compatibility was assessed by isothermal exposure of monolithic ceramics in high temperature gaseous hydrogen plus water vapor.

Strain and Phase Mapping of Ceramic Matrix Composites and Protective Coatings

2014 ◽  
Author(s):  
John Thornton ◽  
Darren Dale ◽  
Matthew Zonneveldt ◽  
Chris Wood ◽  
Jon Almer
Keyword(s):  
High Temperature ◽  
Protective Coatings ◽  
Compressive Strain ◽  
Ceramic Matrix Composites ◽  
High Energy ◽  
Matrix Composites ◽  
Thermal Expansion Coefficients ◽  
Residual Strains ◽  
Tensile Strains ◽  
Sic Coatings

Coatings are frequently required to provide oxidation protection for high temperature materials. Silicon carbide (SiC) coatings have been used to protect carbon-carbon composites on leading edges and zirconia coatings are used as thermal barriers on gas turbine aerofoils. The effectiveness and durability of these coatings is dependent on the residual strains created in these coatings during their formation or deposition and also during service. Tensile strains in the plane of the coating can lead to through thickness cracks that expose the substrate, while compressive strains can cause the coating to delaminate. This paper presents strain measurements of these high temperature material systems obtained with high energy X-ray diffraction. The diffraction also provided useful information on phase, crystallite size and texture as a function of depth. Tensile strains were found in the SiC coatings, and compressive strains were found in the zirconia coatings. Both these strains were parallel to their coatings’ surfaces. The differences in thermal expansion coefficients between the coatings and their substrates can account for both the compressive strain in the zirconia and the tensile strain in the SiC.

Sign in / Sign up

Export Citation Format

Share Document