摘要
以超细WC粉末和超细WC-6Co复合粉末为原料,添加VC/Cr3C2作为晶粒长大抑制剂,同时进行配碳,采用高能球磨和气压强化烧结制备晶粒度小于0.5μm的WC-0.5Co超细硬质合金,研究了不同VC/Cr3C2添加量及配碳量对其组织与性能的影响。结果表明:VC/Cr3C2有效抑制了烧结过程中WC晶粒的长大,显著提高了WC-0.5Co超细硬质合金的硬度。当VC/Cr3C2添加量为0.73%(质量分数,下同)时,合金的硬度(HV0.05)最高,达到32 658 MPa;同时一定的配碳量有利于控制合金中的脱碳,提高合金性能,当配碳量为0.2%时,WC-0.5Co-0.73VC/Cr3C2合金的综合力学性能最好,断裂韧性为6.935 MPa·m1/2,维氏硬度(HV0.05)为32 216 MPa。
The ultrafine WC-0.5Co cemented carbide with a grain size smaller than 0.5 μm was prepared by high energy ball milling and HIP-sintering process. The raw materials were ultrafine WC and WC-0.5Co powder and the additives of grain growth inhibitor were VC/Cr3C2 and carbon. Microstructure and properties of the ultrafine WC-0.SCo cemented carbide with different VC/Cr3C2 and carbon contents were studied. The results show that there is a significant effect of VC/Cr3C2 on controlling WC particle size and hardness of ultrafine WC-0.5Co cemented carbide. Ultrafine WC-0.SCo cemented carbide has best Vickers hardness HV0-05 of 32 658 MPa with the VC/Cr3C2 content of 0.73% （mass fraction, similarly hereinafter）. A certain amount of mixed carbon content is good for decarburization and properties of the ultrafine binderless cemented carbide. Ultrafine WC-0.5Co-073VC/Cr3C2 cemented carbide has best comprehensive mechanical properties with transverse rupture strength of 6.935 MPa·m1/2 and Vickers hardness HV0-05 of 32 216 MPa when the mixed content of carbon is 0.2%.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2015年第4期912-917,共6页
Rare Metal Materials and Engineering
基金
硬质合金国家重点实验室开放课题(201103002)
国家杰出青年科学基金(50925416)
