scholarly journals Melt Infiltrated Ceramic Matrix Composites for Shrouds and Combustor Liners of Advanced Industrial Gas Turbines

2011 ◽  
Author(s):  
Gregory Corman ◽  
Krishan Luthra ◽  
Jill Jonkowski ◽  
Joseph Mavec ◽  
Paul Bakke ◽  
...  
Keyword(s):  
Gas Turbines ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Matrix Composites ◽  
Industrial Gas Turbines

Effect of Microporosity on Damage Initiation in Ceramic Matrix Composites

2019 ◽  
Author(s):  
Suhasini Gururaja ◽  
Abhilash Nagaraja
Keyword(s):  
Gas Turbines ◽  
Ceramic Matrix Composites ◽  
Local Stress ◽  
Ceramic Matrix ◽  
Matrix Composites ◽  
Damage Initiation ◽  
The Matrix ◽  
Homogenization Approach ◽  
Matrix Porosity ◽  
Monolithic Ceramics

Abstract Ceramic matrix composites (CMC) are a subclass of composite materials consisting of reinforced ceramics. They retain the advantages of ceramics such as lower density and better refractory properties but exhibit better damage tolerance compared to monolithic ceramics. This combination of properties make CMCs an ideal candidate for use in high temperature sections of gas turbines. However, modeling the damage mechanisms in CMCs is complex due to the heterogeneous microstructure and the presence of processing induced defects such as matrix porosity. The effect of matrix pore location and orientation on damage initiation in CMCs is of interest in the present work. CMCs fabricated by various fabrication processes exhibit matrix pores at different length scales. Microporosities exist within fiber bundles in CMCs have a significant effect on microscale damage initiation and forms the focus of the current study. In a previous work by the authors, a two step numerical homogenization approach has been developed to model statistical distribution of matrix pores and to obtain the effective mechanical properties of CMCs in the presence of matrix porosity. A variation of that approach has been adopted to model matrix pores and investigate the severity of pores with respect to their location and orientation. CMC microstructure at the microscale has been modeled as a repeating unit cell (RUC) consisting of fiber, interphase and matrix. Ellipsoidal pores are modeled in the matrix with pore distance from the interphase-matrix interface and pore orientation with respect to the loading direction as parameters. Periodic boundary conditions (PBCs) are specified on the RUC by means of constraint equations. The effect of the pore on the local stress fields and its contribution to matrix damage is studied.

Evaluation of Ceramic Rotor Strength by Cold and Hot Spin Tests

1996 ◽  
Vol 118 (1) ◽  
pp. 191-197
Author(s):  
M. Watanabe ◽  
H. Ogita
Keyword(s):  
Gas Turbines ◽  
High Speed ◽  
Maximum Stress ◽  
Bending Strength ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Turbine Rotor ◽  
Matrix Composites ◽  
Burst Test ◽  
High Temperature Condition

Presently in Japan 100 kW ceramic gas turbines (CGT) for automobiles are under development, parts of which include a turbine rotor, scrolls, a combustor, and other parts made of ceramics and ceramic matrix composites. The rotor is designed to rotate at 110,000 rpm, equal to the maximum stress of 300 MPa, and to be exposed to temperatures up to 1350°C. Initially, the strength of ceramic rotors was evaluated by a burst test using a cold spin tester. The burst picture was observed and compared with the 4pt bending strength of the ceramic test specimens. Next, the strength of the rotors was tested by a hot spin test and the burst result of the rotor was evaluated. A high-speed camera was used to observe the rotor at the instant of burst under a high-temperature condition. Applying the result of the cold and hot spin tests, ceramics for turbine rotor were selected and the shape of the rotor was designed.

Ceramic Matrix Composites Application in Automotive Gas Turbines

1997 ◽  
Vol 119 (4) ◽  
pp. 790-798 ◽  
Author(s):  
Takao Izumi ◽  
Hiroshi Kaya
Keyword(s):  
Silicon Carbide ◽  
Silicon Nitride ◽  
Gas Turbines ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Screening Tests ◽  
Particle Impact ◽  
Matrix Composites ◽  
Test Pieces ◽  
Monolithic Ceramics

We are conducting the development of ceramic matrix composites (CMC) and components made of CMC for a 100 kW automotive ceramic gas turbine (CGT) as shown in Fig. 1. When compared to monolithic ceramics (MC), CMC that we have developed demonstrate superior strength characteristics in terms of resistance to particle impact and thermal shock. We have conducted evaluation tests on the strength of CMC components in which MC such as silicon nitride and silicon carbide were used as a reference for comparison with CMC in the same testing process as employed for components made of MC such as silicon nitride and silicon carbide. It was confirmed that actual components made of CMC realized approximately the same strength as the test pieces. Furthermore, some CMC components have already passed screening tests that evaluated the strength of the components. It was therefore confirmed that the potential exists for the possibility of testing these components in high-temperature assembly tests and engine tests.

Ceramic Matrix Composites Application in Automotive Gas Turbines

1996 ◽  
Author(s):  
Hiroshi Kaya ◽  
Takao Izumi
Keyword(s):  
Silicon Carbide ◽  
Silicon Nitride ◽  
Gas Turbines ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Screening Tests ◽  
Particle Impact ◽  
Matrix Composites ◽  
Test Pieces ◽  
Monolithic Ceramics

We are conducting the development of ceramic matrix composites (CMC) and components made of CMC for a 100 kW automotive ceramic gas turbine (CGT) as shown in Fig.1. When compared to monolithic ceramics (MC), CMC that we have developed demonstrate superior strength characteristics in terms of resistance to particle impact and thermal shock. We have conducted evaluation tests on the strength of CMC components in which MC such as silicon nitride and silicon carbide were used as a reference for comparison with CMC in the same testing process as employed for components made of MC such as silicon nitride and silicon carbide. It was confirmed that actual components made of CMC realized approximately the same strength as the test pieces. Furthermore, some CMC components have already passed screening tests that evaluated the strength of the components. It was therefore confirmed that the potential exists for the possibility of testing these components in high temperature assembly tests and engine tests.

Hybrid Oxide-Based CMCs for Combustion Turbines: How Hybrid Oxide CMC Mitigates the Design Hurdles Typically Seen for Oxide CMC

2007 ◽  
Author(s):  
Jay E. Lane ◽  
Jay A. Morrison ◽  
Bonnie Marini ◽  
Christian X. Campbell
Keyword(s):  
Gas Turbines ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Turbine Engines ◽  
Material System ◽  
Matrix Composites ◽  
Gas Turbine Engines ◽  
End User ◽  
Life Goal ◽  
Combustor Liner

Ceramic matrix composites (CMCs), in particular oxide-based systems, are of interest for use in combustion turbines. While uncoated oxide CMCs have significant hurdles to implementation in gas turbines, the Siemens hybrid oxide CMC system is able to overcome these challenges. These hybrid oxide CMCs provide distinct advantages over the current non-oxide based systems. The benefits of hybrid oxide-based systems for advanced gas turbines will be discussed. Material system developments will be discussed including those completed by a Siemens Power Generation led team in a recent NIST (National Institute of Standards and Technology) sponsored program to prove the concept of advanced hybrid oxide-oxide CMCs for gas turbine engines. The program fabricated a full scale outer combustor liner that was installed in a Solar Centaur 50S engine at a commercial end user site. In November 2006, this hybrid oxide CMC outer combustor liner met the target life goal of 25,000 hrs with 25,404 hrs of field test experience. The final hurdle for design of hybrid oxide CMC components is the ability to accurately analytically predict behavior. Methods and approaches to address this challenge are discussed as well.

Evaluation of Ceramic Rotor Strength by Cold and Hot Spin Tests

1994 ◽  
Author(s):  
Makoto Watanabe ◽  
Hiroshi Ogita
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
High Speed ◽  
Bending Strength ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
High Heat ◽  
Turbine Rotor ◽  
Matrix Composites ◽  
Automotive Engine

Presently in Japan 100 kW ceramic gas turbines (CGT) for automobiles are under development, parts of which include a turbine rotor, scrolls, a combustor, and other parts made of ceramics and ceramic matrix composites. The rotor is designed to rotate at 110,000 rpm, equal to the maximum stress of 300 MPa and to be exposed to temperatures up to 1350°C. Initially, the strength of ceramic rotors was evaluated by a burst test using a cold spin tester. The burst picture was observed and compared with the 4pt bending strength of the ceramic test specimens. Next, the strength of the rotors was tested by a hot spin test and the burst result of the rotor was evaluated. A high speed camera was used to observe the rotor at the instant of burst under a high temperature condition. Applying the result of the cold and hot spin tests, ceramics for turbine rotor were selected and the shape of the rotor was designed as a practical automotive engine began in 1990 as a project of the Petroleum Energy Center with financial support from the Agency of Natural Resources and Energy, the Ministry of International Trade and Industry. In order to obtain a 40% or higher thermal efficiency, the automotive gas turbine requires the use of a turbine rotor, combustor, shroud and other engine parts that can withstand high temperatures of 1200°C to 1500°C. In addition, since their resistance to thermal stress and impact are primary considerations, it is necessary to develop high heat-resistant materials (ceramic type materials). Fig. 1 shows a sectional model of the automotive ceramic gas turbine now under development. Under this project, a monolithic ceramic rotor was first evaluated as a turbine rotor. Ceramic matrix composites were then studied.

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