摘要
本文以WC粉、Co粉及Cr_3C_2粉为原料,采用粉末冶金方法制备了不同WC晶粒度、不同Cr_3C_2含量的WC-15%Co硬质合金,通过显微硬度、电化学极化曲线测试,以及金相、扫描电镜观察等试验手段研究了Cr_3C_2含量对不同晶粒度WC-Co合金微观结构和抗腐蚀等性能的影响规律。结果表明,在细颗粒WC-15%Co合金中添加Cr_3C_2后,合金的硬度升高,强度降低;而在粗颗粒WC-Co合金中添加Cr_3C_2后,合金的硬度和强度都将升高。通过Tafel极化曲线测试可以看出WC晶粒度对相同钴含量合金的耐腐蚀性能没有明显线性关系;无论是细颗粒合金还是粗颗粒合金,添加Cr_3C_2均可提高其抗腐蚀性能和细化晶粒。
WC-15%Co cemented carbides with different WC grain sizes and quantities of Cr were prepared by powder metallurgy method, using WC powder, cobalt powder and Cr3C2 powder as raw materials. The effects of Cr3C2 content on the microstructures and corrosion resistance of WC-Co alloys with different grain sizes were investigated by means of microhardness, electrochemical polarization curve, metallographic and scanning electron microscopy. The results show that hardness of the WC-15%Co alloy with fine grain increases but strength decreases with the increase of Cr3C2 addition. On the contrary, the hardness and strength of the WC-15%Co alloy with coarse grain increase with the increase of Cr3C2 addition.There is no obvious liner relationship between WC grain size and the corrosion resistance of the alloys with same cobalt content. Whether it is fine grain alloy or coarse grain alloy, adding Cr3C2 can improve corrosion resistance and refine grain.
出处
《硬质合金》
CAS
2017年第5期300-305,共6页
Cemented Carbides
基金
湖南省自然科学株洲市联合基金资助(项目号2016JJ5041)
