Sintering Behavior and Mechanical and Microstructural Properties of Highly Porous Ti6Al4V Powder Materials

摘要

This paper investigates the sintering behavior of Ti6Al4V compacts containing artificially created large pores and characterizes the microstructure of sintered compacts and its mechanical strength by compression tests. Artificial pores were induced by mixing Ti6Al4V powder with 10 to 50 vol.% ammonium bicarbonate particles of 100-500 μm size. Sintering of porous compacts was performed in a dilatometer in argon. The final porosity varied from 5% to 74%. The microstructure of the samples was examined using scanning electron microscopy and computed micro-tomography (CMT). They allowed a qualitative and quantitative analysis of pore connectivity. Compression tests show exponential increases of the Young's modulus and of the yield stress as function of the volume fraction of salt.