特粗硬质合金开发

Development of Ultra-Coarse Grain Cemented Carbide

采用添加超细复合粉末方法制备出特粗硬质合金,其WC平均晶粒尺寸大于8μm,实验表明:超细复合粉末添加量为10%时,超细WC完全在粗WC上溶解析出,晶粒均匀性最好。此外,针对特粗合金牌号粉料制粒困难的现象,确定了最佳制粒工艺,制得的粉料颗圆度、均匀度较好,粉料具有良好压制性能,满足形状复杂产品压制需求。

In the paper, an u ltra -coarse grain cemented carbide is prepared by adding a kind of ultra - fine composite powders, and in the prepared cemented carbide, the average diameter of the WC grain is more than 8μm. Tests show： When the added ul tra-fine composite powders reach 10%, ul tra-fine WC grains dissolve and precipitate on the coarse WC grain, producing the best grain uniformity. Addi t ional ly, for the fact that grains of ultra-coarse cemented carbide grades are hard to prepare, the best grain preparing process is formulated. As a result, the produced powders offer good roundness, uniformity and press performance, meeting the pressing requirements of products with complex structures.