Method for analyzing mechanical property of UD-CMC (Unidirectional Ceramic Matrix Composite) under stress oxidation environment

A composite material, oxidizing environment technology, applied in special data processing applications, instruments, electrical digital data processing, etc., can solve the problem that the analysis of residual mechanical properties does not consider the effect of stress, etc.

Active Publication Date: 2016-06-01
NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
View PDF5 Cites 29 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] In order to better understand and predict the mechanical properties of CMC in the service environment, the purpose of the present invention is to provide a method for analyzing the mechanical properties of unidirectional ceramic matrix composites in a stress-oxidizing environment, so as to solve the problem of CMC in high temperature in the prior art. The analysis of the change of the remaining mechanical properties does not consider the effect of stress

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for analyzing mechanical property of UD-CMC (Unidirectional Ceramic Matrix Composite) under stress oxidation environment
  • Method for analyzing mechanical property of UD-CMC (Unidirectional Ceramic Matrix Composite) under stress oxidation environment
  • Method for analyzing mechanical property of UD-CMC (Unidirectional Ceramic Matrix Composite) under stress oxidation environment

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0078] The present invention will be further described below in conjunction with the accompanying drawings.

[0079] The study found that due to the brittleness of the ceramic matrix, the failure process of the UD-CMC matrix under stress is as follows: 1) a "crack source" is formed in the matrix under stress; 2) the "crack source" expands to form cracks; 3 ) A new "crack source" is formed, and the crack continues to expand to become a through crack; 4) The number of cracks no longer increases, and the cracking of the matrix reaches a saturated state.

[0080] In the high temperature environment, the effect of stress on the mechanical properties of UD-CMC is mainly reflected in the increase of the effective area of ​​oxidation. There are mainly the following two ways: 1) the number of cracks increases as the stress increases; 2) the crack width increases as the stress increases. Therefore, the present invention mainly divides into the following several steps to the analysis of...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for analyzing the mechanical property of a UD-CMC (Unidirectional Ceramic Matrix Composite) under a stress oxidation environment. The method comprises the following steps: determining the crack number, which changes along with stress, of a base of the UD-CMC; determining a crack width change rule; determining influence of cracking of the base of the UD-CMC on the change of a mass weight-loss ratio lambda by considering a stress reaction according to an oxidation mechanism of the UD-CMC under an existing unstressed oxidation environment of 400 to 900 DEG C; determining a change rule of residual modulus of the UD-CMC under a stress oxidation environment by considering the situation that the base of the UD-CMC cracks; determining a change situation of residual strength of the UD-CMC under the stress oxidation environment by considering the situation that the base cracks according to a change rule of the volume fraction of the UD-CMC. According to the method for analyzing the mechanical property of the UD-CMC under the stress oxidation environment, disclosed by the invention, a relevant theoretical support is provided for analyzing the mechanical property of the UD-CMC under the stress oxidation environment.

Description

technical field [0001] The invention relates to a theoretical method for analyzing the mechanical properties of a unidirectional ceramic matrix composite (UD-CMC), which is mainly used for analyzing the prediction of the remaining mechanical properties of the unidirectional ceramic matrix composite in a stress oxidation environment. Background technique [0002] In order to achieve a high thrust ratio of aero-engines, increase the temperature before the turbine and reduce the mass of the engine, CMC is an ideal material for high-temperature components of aero-engines. Due to the harsh service environment of CMC, it is often affected by high temperature, high stress, thermal shock and corrosive gas, which greatly reduces the performance of the material. Stress and high temperature are the two most typical environmental factors in the service environment of CMC. It is necessary to consider the change of mechanical properties of CMC under stress-oxidation environment. [0003...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G06F17/50
CPCG06F30/367
Inventor 孙志刚邵红艳宋迎东
Owner NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products