超细晶硬质合金刀具Co含量对其耐磨损性的影响

Effect of Cobalt Content on Wear Resistance of Ultrafine Cemented Carbide Tools

用不同Co含量的超细晶硬质合金刀具对高温合金GH2132进行了高速连续切削试验,根据最小二乘法对试验结果进行了线性回归,建立了刀具寿命与切削速度之间的关系即T-υc经验公式;随后进行了高速断续切削刀具磨损试验,用连续变倍体视显微镜及显微摄影系统观察了刀具刃口和后刀面的磨损形貌,并对达到磨钝标准时的刀具后刀面磨损微区成分进行了电子探针能谱分析,探讨了粘结相Co含量对刀具磨损性能的影响机理。结果表明:粘结相Co含量过高或过低,均会降低刀具的耐磨损和破损性能。

High-speed continuous cutting test was carried out with different cobalt content of ultrafine cemented carbide tools to cut the superalloy GH2132.Based on linear regression of the test results with the least square method,the T-vcempirical formula was set up reflecting the relationship between tool life and cutting speed.And then tool wear test was carried out by high-speed intermittent cutting.Wear morphologies of tool edges and flank faces were observed with zoom stereomicroscope and photomicrography system.When the tool achieved the wear criterion,the composition of its flank wear micro-zone was analyzed by electron microprobe spectroscopy.The mechanism was discussed of cobalt content influencing tool wear resistance.The results show that both too high and too low cobalt content would result in poorer tool wear and breakage resistance.