氩弧重熔对D型石墨铸铁表面耐磨性的影响  

Influence of Argon Arc Remelting on Surface Abrasion Resistance of D-type Graphite Cast Iron

作　　者：鲍爱莲 刘万辉 胡天润 徐一 BAO Ailian;LIU Wanhui;HU Tianrun;XU Yi(School of Automotive Engineering,Changshu Institute of Technology,Changshu 215500,China)

机构地区：[1]常熟理工学院汽车工程学院,江苏常熟215500

出　　处：《热加工工艺》2020年第10期89-91,共3页Hot Working Technology

基　　金：江苏省自然科学基金青年基金项目(BK20160407);常熟理工学院校级科研项目(QZ1602、XZ1502)。

摘　　要：D型石墨铸铁因其良好的性能,广泛应用于汽车缸体、缸套、凸轮轴、模具等零部件,在其使用过程中,通常需要具有良好的表面耐磨性。进行了不同重熔电流的D型石墨铸铁氩弧重熔强化工艺对比。利用显微硬度计、磨损实验机测试了表面硬度和磨损现象;利用金相显微镜、扫描电镜分析了重熔电流对重熔层组织与磨损形貌的影响。结果表明:D型石墨铸铁经氩弧重熔后可获得硬度高、耐磨性好的表面强化层;重熔区组织主要有树枝状(M+A’)+低温莱氏体(M+A+碳化物);在一定工艺参数范围内,重熔电流90 A、重熔速度3.5 mm/s、气流量在10 L/min时,其耐磨性能达到最佳;D型石墨铸铁氩弧重熔表面的摩擦磨损机制以磨粒磨损为主。D-type graphite cast iron is widely used in automobile cylinder body, cylinder sleeve, camshaft, mold and other parts due to its good performance. The cast iron parts are usually required to have good wear resistance during the operation.The argon arc remelting process of D-type graphite cast iron under different remelting currents was compared. The surface hardness and wear behavior of the samples were tested by microhardness tester and wear machine. The effects of remelting current on the structure and wear morphology of the remelting layer was furtherly analyzed by OM and SEM. The results show that the surface strengthening layer with high hardness and good abrasion resistance on the D-type graphite cast iron can be obtained by argon arc remelting treatment. The microstructure of remelting zone is mainly dendritic(M +A’) and modified Ledeburite(M+A+carbide). In the range of parameters, the surface wear resistance of D-type graphite iron argon arc remelting layer is best with 90 A remelting current, 3.5 mm/s remelting speed and 10 L/min gas flow. The friction and wear mechanism of D-type graphite iron argon arc remelting surface is mainly abrasive wear.

关 键 词：D型石墨铸铁 氩弧重熔 硬度 耐磨性 

分 类 号：TG174[金属学及工艺—金属表面处理]