Analysis on the field of temperature and thermal stress for Al2O3/Ti system FGM during laser sintering

We use finite element method to calculate temperature field and thermal stress field for Al2O3/Ti system FGM in the process of laser sintering.The temperature of the different layers of the sintering sample was measured with the thermocouples.The results show that the temperature drop between the laser irradiating surface(Al2O3/Ti layer) and the back surface(Ti layer) was 325℃,and the temperature gradient was more precipitous in Al2O3 ceramic layer than in Ti metal layer.We defined the parameter p,called component gradient of FGM sample,to indicate the level of the temperature gradient in ceramic Al2O3 layer.The thermal residual stress distribution mainly was dependent on the value of p.The axial shear stress occurred near the radial free edge,and transformed from compressive stress to tensile stress along with the increasing of p from less than 0.5 to greater than 0.5.The maximum radial stress occurred in the transition region between pure Al2O3 layer and graded interlayer.The distribution of circumferential stress was similar to radial stress distribution.All of the component of the thermal residual stress got the minimum when p=0.5.