Transformation of metal surface to cermet by plasma processing and powder/granular material holder for ion implantation

摘要

This experimental study is concerned with the fabrication of "cermets" at a sub-surface layer of metal by reactive plasma processing at high temperatures. Samples of Ti and Zr were carbonized or nitrided with use of CH{sub}4 gas or a gas mixtureof N{sup}2 and H{sub}2, respectively. Experiments were done below 1300℃ for less than 3h. Thickness and hardness of modified layers were increased with the modifying time and temperature, especially, at temperature over 900℃. The maximum Vicker'shardness of TiC based cermet was about 5000Hv (kg/mm{sup}2) and the maximum thickness of ZrN reached about 50μm for only 2 h, both at 1300℃. For the next step aiming to decrease the activation energy of atomic diffusion and the modifying temperature,the effects of pre-irradiation processing before the main processing were reviewed for the nitriding of pure aluminium. In addition, relating to the application of ion implantation to the fabrication of cermets by sintering, "a powder/granular materialholder" was newly designed.