화학공학소재연구정보센터
Materials Science Forum, Vol.386-3, 403-408, 2002
Microstructural investigation of grain stability in cryomilled Inconel 625
The grain growth behavior of nanocrystalline Inconel 625 powders prepared by cryomilling (mechanical milling under a liquid nitrogen environment) was investigated using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The average grain size of powders after 8 hours cryomilling was 22 nm. Along with this fine structure, ultrafine NiO and Cr2O3 oxide particles were distributed in the cryomilled material with average size of 3 rim. It was found that the grain size remain under 250 nm after 4 hours heat treatment at 800degreesC, which correspond to T/T(m)similar to0.65. The cryomilled Inconel 625 showed improved grain stability compared to that of conventional Inconel 625 and cryomilled pure-Ni, due to the particle pinning of grain boundary by the oxide particles in addition to solute drag.