热处理对硬质合金结构参数的改变

硬质合金的质量在很大程度上受其显微组织的影响,使用适宜的热处理工艺可以使圆滑状棱角的晶粒数量增加,从而改变W C邻接度,使硬质合金的塑性变形能力得到提高,改善了合金的性能。研究了回火工艺对热处理产品的影响,系统地分析了回火时过饱和固溶体的析出物,从而制定合适的回火工艺。同时,探讨了热处理对硬质合金疲劳极限的影响,并通过大批量合金的冲击韧性验证以及用户使用实验证明,热处理合金具有较高的冲击韧性,在循环冲击条件下,热处理合金有较高的使用性能。

The variation on structure parameter of cemented carbide by heat treatment

The quality of cemented carbide was influenced,to a considerable degree,by its microstructure.The process of heat treatment affects the crystal angularity of WC phase: the degree of the rounding of the edges and corners of carbide crystals tends to increase,which varies the contiguity of WC crystal,thus the properties of alloy improved.It has been investigated that the process of annealing influences the properties of carbides,and that the precipitated phase separated from supersaturated solid solution.So the optimum process of annealing was implemented.Also,it was explored that the heat treatment process influences the fatigue limit of alloy.After a great deal of experiments on the check of impact strength and field experiments,it was concluded that the alloy after heat treatment has great advantages on property under the condition of cyclical impact.