SiC_f/TC17 Composites Interface Microstructure And Performance Research

Continuous SiC fiber reinforced titanium matrix composites with high specific strength and modulus,at the same time has good high stability performance and fatigue performance,used to make blade and casing aerospace components,is an important part of the whole blade ring,reduce weight and improve the efficiency of the flight,will cause great change of engine design.This paper adopts the combining fiber coating materials with hot isostatic pressing process of the preparation of SiC_f/TC17,using optical microscope,scanning electron microscopy(SEM),electron probe,energy spectrometer and nanoindentor for short-term heat exposure under 450?condition of SiC_f/TC17 microstructure,interface composition,interface element diffusion and micromechanical properties are analyzed.The results show that the short-term heat under 450? exposure is not obvious effects on the matrix microstructure,has a little influence on thermal stability of materials,each part of the material of the micro hardness and elastic modulus has no obvious change,chemical reaction diffusion is the main reason of the formation of reaction,the interfacial reaction layer in compliance with Arrhennius law.Finite element simulation of the interfacial residual stress results show that the interface between the increase of fiber volume fraction can lead to ring to the residual stress value decreases the radial residual stress value increase;C coating and the change of the thickness of reaction layer of hoop stress influence small and big effects on radial stress;Ring to the maximum stress at 0o and 60o,size of 572 MPa,the minimum stress in 30o and 90o,size of523MPa;Radial stress amplitude along with the change of angle is bigger than to stress,the maximum stress at 30o and 90o,size of 188 MPa,the minimum stress at 0o and 60o,size of82 MPa.Both to stress at the interface is one of the biggest,in the intermediate position of the two fiber is minimal.SiC_f/TC17 at ambient temperature and high temperature tensile fracture process is similar,the difference is in the process of the high temperature tensile fracture of fiber pull out and debonding are more than the room temperature tensile fracture;High temperature fatigue fracture process of fatigue source in the junction of sheath and composites,the ductile fracture in matrix is more than high temperature tensile failure,the last of the overload fracture is similar to high temperature tensile overload fracture.