脱脂与烧结工艺对WC-6Co-1TaC硬质合金显微结构与性能的影响

采用“溶剂脱脂+烧结”方法制备WC-6Co-1TaC硬质合金;研究了在同一烧结工艺下不同溶剂脱脂率对合金显微结构与性能的影响;以及在相同或相近的溶剂脱脂率下不同烧结工艺对合金显微结构与性能的影响;实验结果表明:高的溶剂脱脂率有利于获得更高性能的合金,溶剂脱脂率为41%的脱脂坯经烧结工艺A后较脱脂率为38%的试样抗弯强度提高16%,渗碳程度减轻,孔隙减小;烧结时在低温热脱脂阶段延长保温时间有利于残余粘结剂的排除和高温阶段通过进一步延长抽真空时间净化炉内气氛可以减轻渗碳程度从而提高合金性能。溶剂脱脂率为41%经烧结工艺B后制备的合金较经烧结工艺A制备的合金强度提高17%,达1684 MPa。

Effects of Debinding and Sintering Process on Microstructure and Properties of WC-6Co-1TaC

The experiment adopts "Solvent debinding+sintering" to prepare WC-6Co-1TaC cemented carbide.Based on the research on the effect of different debiding removal rate on microstructure and properties on the condition of the same sintering process and the effect of different sintering processes on microstructure and properties with the same debinding removal rate,Which shows that the properties of alloy would be better with higher debiding removal rate.The sample with solvent debinding removal of 41% has increased the transverse rupture strength by 16%,lightened carburization,decreased porosity compared with that of solvent debinding removal of 38% prepared by the same sintering process A;Delaying binder removal time would remove residual binder at low temperature sintering,and delaying the time of drawing vaccum properly would purify the atmosphere in funace at high temperature sintering,.By means of these methods,caburization would be lightened and the properties of alloy would be improved.The alloy which has solvent debinding removal of 41% and prepared by sintering process B increased the transverse rupture strength by 17% compared with the product prepared by sintering process A and the transverse rupture strength has reached 1684 MPa.