Mechanics Analysis On Functionally Graded Material And Bi-material Of SiC/Al

Functionally graded material (FGM) is a new type of composite with broad application to many fields nowadays. It improves joint strength between two different materials with the structural character of continuous transition. And ceramic/Metal FGM has been focus by many researchers for its excellent capability of reducing thermal stress. In this paper, mechanics property on SiC/Al FGM and bi-material in room and high temperature was investigated by use of experiment and numerical simulation. It would provide experimental information for the application of this material in engineering.In this paper, the temperature field and stress field in SiC/Al weld process were simulated by FEA software ANSYS firstly. Then the distribution of residual stress was obtained.Secondly, FGM specimen with four gradient layers was produced by infiltration technique. Then strain distribution of FGM specimen subjected to thermal and concentrated load was tested by Moire interferometry. In additionally, numerical result was calculated by ANSYS software on FGM and bi-material in same conditions. The comparison of experimental results with numerical results of FGM shows that moire interferometry is a feasible way to test reliable strain on FGM. And it would provide useful experimental data for preparation of FGM. By contrasting FGM with bi-material, it turns out that FGM has the advantage of reducing thermal stress.In additionally, fracture mechanics on FGM was researched by experiment and simulation in the paper. Three-point bending specimen containing a crack parallel to gradient direction was used in experiment to discuss the crack propagation and calculate fracture toughness K_IC Fracture problem containing a crack perpendicular to gradient direction was discussed by compact tension experiment. Moreover, the relation of stress intensity factor K₁ and load was presented by finite element analysis.