Microstructure and Mechanical Properties of Extra Coarse Grained Hardmetals

摘要：

　　Extra coarse grained hardmetals with Co content of 7wt% and 10wt% were prepared by vacuum sintering with extra coarse WC and spherical cobalt powders as starting materials.Metallic phases and microstructure of these hardmetals were observed by optical microscope (OM) and field-emission scanning electron microscope (FESEM),respectively; mechanical properties of extra coarse grained hardmetals and the correlations between mechanical properties and microstructure parameters were obtained.The results show that most extra coarse WC grains are rounded or equiaxed and the contiguity of WC decreases slightly with the WC grain size increasing; the calculated critical crack lengths are almost equal to extra coarse WC grain sizes,which lead to poor transverse rupture strengths (TRS) of the extra coarse grained hardmetals; extra coarse rounded WC grains and thick cobalt interlayers lead to bifurcating,diverging and discontinuous cracks and enhancement of rupture toughness (K1c) of the hardmetals.

关键词： hardmetal extra coarse microstructure mechanical property critical crack

作者: Wu Chonghu Nie Hongbo Zeng Qisen Xiao Mandou Guo Shiju

作者单位: China National R&D Center for Tungsten Technology,Xiamen Tungsten Co.,Ltd.Technology Center,Xiamen 3 China National R&D Center for Tungsten Technology,Xiamen Tungsten Co.,Ltd.Technology Center,Xiamen 3 School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100

会议类型: 国际会议

会议名称: 2012 Zhuzhou International Conference on Cemented Carbides(株洲硬质合金国际学术会议)

会议地点: 株洲

会议语种:英文

页码: 151-157

在线出版日期: 2012-09-12（万方平台首次上网日期，不代表论文的发表时间）