Sintering metal powders such as iron - using pressure and temp. cycling round structural transformation point to create superplasticity

摘要

Process for mfg. a sintered object or compact, the novelty being that a metal powder is sintered with the creating or the control of superplastic phenomena, by subjecting the compact to a temp. cycle which passes through the transformation point of the metal powder while pressure is simultaneously applied to the compact. The process can be employed with a metal powder contg. one or more constituents and sintered below its m. pt. for a short time which can be undertaken in air as a controlled atmos. is not essential to prevent oxidn. The process is used e.g. for the mfr. of heat-exchanger panels, cores for heating pipes, extremely hard gear wheels etc. The porosity of the compact and also its density can be controlled.