Characteristics of residual stress in Mo–Ti functionally graded material with a continuous change of composition

With the addition of the sintering additives Ni and Cu, highly dense Mo–Ti alloys with various Mo:Ti ratios were obtained by hot-pressing method. Under the same conditions a Mo–Ti green body with continuously graded composition, formed by the particle settling method, was sintered. The longitudinal and transverse ultrasonic velocities of Mo–Ti alloys were tested in order to calculate the residual stresses that develop during cooling of the Mo–Ti functionally graded material (FGM). By using an axisymmetric finite element method, the fabricated thermal stress in a disk-shaped Mo–Ti FGM was calculated. The results show that the residual stress continuously changes with the smooth change of graded composition and the maximum value of residual tensile stress is far lower than that of the bending strength of Mo–Ti alloys.