Effect of milling time on synthesis TiB2-TiC/Ni cermet by MASHS

TiB2-TiC/Ni cermet was prepared by Mechanical-Activated Self-Propagating High- Temperature Synthesis (MASHS). Ti , B4C and Ni powders were milled at 1 , 3 and 6 h in plantary ball mill with 10/1 BPR and 300 rpm milling speed an in Ar environment. After milling process, milled powders were formed to pellets by uniaxial press. Then green compacts were synthesized in tube furnace at Ar atmosphere and 1000 , 950 , 900 °C temperatures. The results of synthesis process showed that the ignition time and ignition temperature were decrease by increase of milled powders milling time , while sample was milled at 6 h, it could be synthesized in 900 °C but when samples were milled at 1 and 3 h were synthesized only at 1000 °C. In next step samples were analyzed by XRD. XRD results show that no any phase was formed in milling process and intensity of B4C peaks was reduce by increasing of milling time. On the other hand, favorable phases peaks such as TiB2 and TiC with Ni were seen on the synthesized samples patterns. Crystallines size were calculated by using Williamson_Hall method, result in the average of crystallines size of TiB2 and TiC in samples with 20% wt Ni were 53nm and 25nm respectively.

کلیدواژه ها:

cermet ، Mechanical-Activated ، SHS ، milling time ، TiB2 ، TiC ، Ni