WC碳量对WC-6%Ni硬质合金组织与性能影响  

Effect of Carbon Content in Tungsten Carbide on Microstructure and Properties of WC-6%Ni Cemented Carbide

作　　者：罗成 梁小东 唐冬梅 杨文强 王金林 曹志华 Luo Cheng;Liang Xiaodong;Tang Dongmei;Yang Wenqiang;Wang Jinlin;Cao Zhihua(Seed Technologies Corp.Ltd.,Zhuzhou Hunan 412000,China)

机构地区：[1]西迪技术股份有限公司,湖南株洲412000

出　　处：《硬质合金》2022年第3期195-201,共7页Cemented Carbides

摘　　要：选用总碳含量为5.90%(不饱和碳,质量分数,下同)和6.15%(饱和碳)两种WC原料,分别配制WC-6%Ni硬质合金的橡胶混合料和石蜡混合料并压制成压坯,通过调整压坯的脱胶和脱蜡条件来改变合金的相对磁饱和,使合金具有二相(WC+Ni)或三相(WC+Ni+η和WC+Ni+C)结构,对比研究了在相对磁饱相当的状态下,不饱和碳化钨原料和饱和碳化钨原料对WC-6%Ni硬质合金的组织结构与性能的差异。结果表明:WC-Ni硬质合金的比饱和磁化强度较低,但仍然和WC-Co硬质合金类似可以作为衡量合金碳含量高低的指标,其极限相对磁饱和值约为90%左右;不饱和碳化钨原料由于W2C相的存在,制得的合金组织受碳含量影响敏感,极易出现异常粗大晶粒的情况;在无磁状态、且处于二相结构时,不饱和碳化钨原料制得合金的密度、硬度、抗弯强度都稍高于饱和碳化钨原料制得合金;在相对磁饱和约80%、且处于二相结构时,不饱和碳化钨原料制得合金的密度、硬度稍高于饱和碳化钨原料制得合金,但饱和碳化钨原料制得合金的抗弯强度比不饱和碳化钨原料制得合金高19.4%。生产实践中,应选用饱和碳的碳化钨原料生产WC-Ni硬质合金以获得均匀的组织结构,并提高其综合性能。Two kinds of tungsten carbide(WC)raw material with a respective carbon content of 5.90%(unsaturatedcarbon,mass fraction,the same below)and 6.15%(saturated carbon)were used to manufacture the rubber binder mixture andparaffin binder mixture of WC-6%Ni cemented carbides separately,and they were pressed into green compacts.Then,therelative magnetic saturation of the cemented carbides was changed by the adjustment to the debonding and dewaxingconditions of the green compacts to ensure that the cemented carbides presented two-phase(WC+Ni)or three-phase(WC+Ni+ηand WC+Ni+C)microstructure.Finally,a comparative analysis was performed on the differences in microstructureand properties of WC-6%Ni cemented carbides prepared by unsaturated carbon raw material and saturated carbon rawmaterial in the state of equivalent relative magnetic saturation.The results reveal that the WC-Ni cemented carbide has lowspecific saturation magnetization,but similar to the WC-Co cemented carbide,it can be used as an indicator to measure thecarbon content of cemented carbides,and its ultimate relative magnetic saturation is about 90%.Due to the existence of theW2C phase in unsaturated carbon raw material,the microstructure of the prepared cemented carbide is sensitive to the carbon content,and abnormal coarse grains are prone to occur.The density,hardness,and bending strength of the cemented carbideprepared by unsaturated carbon raw material are slightly higher than those of the cemented carbide prepared by saturatedcarbon raw material when the cemented carbides are in the non-magnetic conditions with a two-phase microstructure.Whenthe relative magnetic saturation is about 80%,and the microstructure is in a two-phase condition,the density and hardness ofthe cemented carbide prepared by unsaturated carbon raw material are slightly higher than those of the cemented carbideprepared by saturated carbon raw material.Nevertheless,the bending strength of the cemented carbide prepared by saturatedcarbon raw material is 19.4%higher than that of the cem

关 键 词：WC WC-Ni硬质合金 相对磁饱和 硬度 抗弯强度 

分 类 号：TG135.5[一般工业技术—材料科学与工程]