论文部分内容阅读
本文在WC-8%Co(文中含量均为质量分数)、复合抑制剂(VC/Cr3C2)的基础上,添加不同配比的Cr3C2及(W,Ti,Ta)C,制备超细硬质合金。采用横向断裂强度检测、洛式硬度检测、SEM分析、TEM检测等方法,研究了Cr3C2和(W,Ti,Ta)C对超细硬质合金力学性能和组织结构的影响。结果表明:随着Cr3C2、(W,Ti,Ta)C的增加,晶粒大小没有显著变化,硬质合金的横向断裂强度减低,硬度提高。通过透射电镜观察,在WC-8%Co-4%(W,Ti,Ta)C-0.5%(VC/Cr3C2)硬质合金中发现了类似于孪晶的结构,并通过能谱证实了Cr3C2和(W,Ti,Ta)C的存在。WC-8%Co-4%(W,Ti,Ta)C硬质合金经1 390℃压力烧结后,硬度为93.8 HRA,抗弯强度为2 250 MPa,相对密度为99.7%。
In this paper, different proportions of Cr3C2 and (W, Ti, Ta) C were added to WC-8% Co (VC and Cr3C2) . The effects of Cr3C2 and (W, Ti, Ta) C on the mechanical properties and microstructure of ultrafine cemented carbide were studied by transverse rupture strength test, Rockwell hardness test, SEM analysis and TEM test. The results show that with the increase of Cr3C2, (W, Ti, Ta) C, the grain size does not change significantly, the transverse rupture strength decreases and the hardness increases. The structure of twin-like structure was found in the WC-8% Co-4% (W, Ti, Ta) C-0.5% (VC / Cr3C2) cemented carbide by transmission electron microscopy and the Cr3C2 And (W, Ti, Ta) C. The hardness of WC-8% Co-4% (W, Ti, Ta) C cemented carbide sintered at 1 390 ℃ is 93.8 HRA, the flexural strength is 2 250 MPa and the relative density is 99.7%.