放电等离子烧结制备无粘结相SiC<sub>w</sub>/WC硬质合金

放电等离子烧结制备无粘结相SiC_w/WC硬质合金

摘要: 以碳化硅晶须（SiC whiskers，SiC_w）作为增韧相，通过放电等离子烧结制备了无粘结相SiC_w/WC硬质合金。考察了放电等离子烧结温度及SiC_w添加量对SiC_w/WC硬质合金组织性能的影响。结果表明，采用放电等离子烧结在1800 ℃下可获得相对密度高于99%的WC烧结体，其维氏硬度和断裂韧性分别达到25.99 GPa和4.99 MPa∙m^1/2。添加适量的SiC_w可以改善SiC_w/WC烧结性能和断裂韧性，在SiC_w的质量分数为0.6%时，断裂韧性达到6.80 MPa∙m^1/2，当添加过量的SiC_w时，增韧效果减弱。

Abstract: SiC whiskers (SiC_w)/WC binderless cemented carbides were prepared by spark plasma sintering (SPS), using SiC_w as the toughening phase. The effects of sintering temperature and SiC_w content on the microstructure and properties of the SiC_w/WC cemented carbides were investigated. The results show that the WC sintered body with the relative density higher than 99% can be obtained by spark plasma sintering at 1800 ℃, and the Vickers hardness and fracture toughness reach 25.99 GPa and 4.99 MPa∙m^1/2, respectively. The sintering properties and fracture toughness of the SiC_w/WC sintered body can be improved by adding the appropriate amount of SiC_w. The fracture toughness reaches 6.80 MPa∙m^1/2 with the SiC_w mass fraction of 0.6%. However, the toughening effect to the WC matrix decreases with the further increase of content SiC_w.