超细晶硬质合金用原料Co粉的选择  

Choice of cobalt powder used in ultrafine cemented carbide

作　　者：竭正强 杨跃 杜伟 吴冲浒 

机构地区：[1]厦门金鹭特种合金有限公司,厦门361006 [2]厦门钨业股份有限公司技术中心,厦门361009

出　　处：《粉末冶金材料科学与工程》2010年第6期644-649,共6页Materials Science and Engineering of Powder Metallurgy

基　　金：国家科技支撑计划资助项目(2007BAE05B02)

摘　　要：除球磨时间、碳含量、抑制剂及烧结方式对超细晶硬质合金的性能影响较大外,WC粉和Co粉原料的选择也对超细晶硬质合金有重要的影响。采用不同球形度、氧含量和硫含量的Co粉作为粘结相,在相同的工艺条件下,制备成分相同的超细晶硬质合金。通过考察制备合金的抗弯强度(TRS)、断裂韧性(KIC)和HV30等力学性能,评定不同Co粉对合金性能的影响。结果表明:在相同的工艺条件下,随着球形度增加,Co粉在混合料中分布更均匀,合金的TRS随之提高,但硬度和KIC变化不大;合金的TRS和硬度随着Co粉松装密度的增大略有下降;Co粉中氧含量及杂质(如S等)含量对超细晶硬质合金性能影响重大,过量的氧和杂质能使超细晶硬质合金综合性能大幅降低。Except for the milling time,carbon content,inhibitor and mode of sintering,the raw material such as WC powder and cobalt powder also influence the properties of ultrafine cemented carbide essentially.The ultrafine cemented carbides were prepared in same process condition using the cobalt powders with different morphology,oxygen content and sulfur content.The mechanics properties,such as TRS,KIC and HV30,were investigated.The results show that the distribution homogeneity degree of cobalt powders in ready to press powder（RTP） improves with their sphericity increasing and the TRS of cemented carbides also increases.However,the hardness and the fracture toughness change little when sphericity of Cobalt powders is adjusted.The hardness and the fracture toughness of cemented carbides decrease slightly with the increasing of bulk density of cobalt powder.The oxygen content and impurities（for example,surfur） content of cobalt powder influence the properties of ultrafine cemented carbide hugely,overabumdant oxygen and impurity can make the properties decreasing terribly.

关 键 词：超细晶硬质合金 Co粉形貌 松装密度 氧含量 硫含量 

分 类 号：TF125.3[冶金工程—粉末冶金]