等离子钇钨钼共渗表面冶金高速钢的研究

Preparation of Surface Metallurgy Y-W-Mo High Speed Steel

利用双层辉光等离子渗金属技术,以稀土钇、钨、钼作为源极,在Q235钢表面进行钇钨钼共渗,形成均匀致密合金扩散层,然后进行固体渗碳、淬火及低温回火处理,形成钇钨钼表面高速钢。用显微硬度仪检测表面高速钢的硬度,通过SEM、XRD观察分析钇钨钼高速钢形貌和相结构,并采用GZTC-01型磨损试验机对钇钨钼高速钢进行耐磨性实验。研究结果表明：进行等离子钇钨钼共渗,可获得数十微米的共渗合金层,共渗合金层为均匀固溶体层,组织形貌为柱状态晶体,基体与渗层之间有明显的反应扩散分界线,渗层与基体是冶金结合,无剥落现象,具有较好的成分和结构梯度;共渗合金层渗碳淬火及回火后,无共晶碳化物产生,组织为隐晶马氏体上分布均匀的细小、弥散碳化物,碳化物尺寸小于1μm,稀土钇在晶界富集并形成颗粒状碳化物;渗碳淬火及回火后钇钨钼表面高速钢表面硬度为1 000 HV0.1左右,比单纯钨钼表面高速钢表面硬度高出200 HV0.1;钇钨钼表面高速钢试样的耐磨性是表面钨钼高速钢试样的2~4倍,是T10钢750℃淬火回火处理工艺试样的10倍左右。

Co-diffusion of Y-W-Mo was conducted on the surface of Q235 steel by means of t he double glow plasma surface alloying technique.This method can form a uniform dense alloy diffusion layer through double glow plasma surface alloying technique in the surface of Q235 steel.Then the Q235 steels amples were solid carburized 、quenched and tempered treatment;At last,the Y-W-Mo high speed steel layer was formed on the surface of Q235 steel.the hardness of the surface of high speed steel layer was detected by microhardness;the analysis of morphology and phase structure of Y-W-Mo high speed steel layer used SEM and XRD;the experiment of wear resistance is carried on with GZTC-01 wear tester.The results show that： plasma Y-W-Mo alloying were available to tens of microns alloying layer,which is uniform solid solution alloying layer,the Morphology is the crystal for a column,there was a boundary of reaction diffusion between the matrix and the diffusion layer,while diffusion layer and the substrate is metallurgical bonding,no spalling and good composition and structure gradient;After carburized、quenched and low tempered,alloying layer didn＇t produce any eutectic carbides,Fine uniformity carbon The Microstructure is the hidden Markov crystal body on which distribut small,dispersed carbide,the size of which is less than 1μm,rare-earth yttrium enrichment at the grain boundaries and form granular carbide;After carburized quenched and tempered,the surface hardness of Y-W-Mo high speed steel layer is HV0.11,000 or so,which is higher than the surface hardness of W-Mo high speed steel layer HV0.1200;the wear resistance of Y-W-Mo high speed steel layer is 2 to 4 times than W-Mo high speed steel samples,which of is 10 times than the samples of T10 steel quenched 750 ℃ and tempered process.