Abstract:The prealloyed powder metallurgy (PM) process and HIP technology and PREP powders are used to
prepare full density PM TC11 (Ti-6. 5Al-3. 5Mo-1. 5Zr-0. 3Si) alloy, a kind of heat resistant titanium alloy. Heat
treatment is studied to optimize the microstructures and properties of the PM TC11 alloy. The microstructures are examined by optical microscope, and the morphologies of PREP powders are observed by SEM. Room temperature and
high temperature (550) tensile properties and elastic modulus of PM TC11 alloy are tested and discussed. The mi
crostructures and properties of the PM TC11 alloy are compared with those of the same batch forged rod. Nearnetshape processes are studied to fabricate PM TC11 parts. By using of special dies, a big dimension thin wall integrated
PM TC11 alloy spacecraft cabin with inner gridding stiffening ribs is nearnetshaped and no inner defect is detected.
The results show that the PM TC11 alloy has the same good tensile properties as forged material and plus perfect elas tic modulus. The microstructures of the PM TC11 alloy are fine and uniform and the typical ones are basketweave
structures surrounded by equiaxed The PM TC11 alloy and suitable nearnetshape process can be used in the field of fabricating high performancetocost, high reliability, lightweight and heat resistant parts for spacecrafts.