机械合金化制备WC—Co纳米硬质合金

本文利用机械合金化技术研究了ＷＣ－Ｃｏ的合金化过程，成功地制备出纳米ＷＣ－Ｃｏ合金粉末，通过真空烧结成型工艺获得了平均晶粒度小于２００ｎｍ的ＷＣ－Ｃｏ硬质合金，其硬度达到１７．４ｋＮ／ｍｍ２，烧结密度为１０．９ｇ／ｃｍ３．对纳米ＷＣ－Ｃｏ粉末的烧结工艺作了初步探讨，通过添加少量的ＶＣ能有效地抑制烧结过程中晶粒的长大．

Formation of Nanostructured WC Co Cemented Carbide by Mechanical Alloying

Nanocrystalline WC Co cemented carbide powder was directly synthesized by mechanical alloying, and the structure evolution of the powder was monitored by X ray diffraction and scanning electron microscope. Milled powders of WC Co were compacted and sintered. The hardness and sintered density were measured to be 17.4 kN/mm 2 and 10.9 g/cm 3 respectively. The sintered time dependence of WC Co grain size was presented. It is found that an appropriate amount of VC addition can improve the thermal stability of WC Co and reduce the growth rate of WC crystallites.