提高15%Cr-2%Mo过共晶白口铸铁耐磨性能研究  

Investigation of Improving Wear Performance of Hypereutectic 15%Cr-2%Mo White Irons

作　　者：R. Reda A. Nofal Khaled Ibrahim A. Hussien 田桦萌 

机构地区：[1]埃及中心冶金开发研究所,Helwan,Egypt [2]埃及开罗大学工程学院,Giza,Egypt [3]不详

出　　处：《铸造》2010年第12期1244-1250,共7页Foundry

摘　　要：本研究的主要目的是优化15%Cr-2%Mo过共晶白口铸铁的冲击韧性和耐磨性。研究了动态凝固、铌元素添加和二者共同作用及热处理的影响。采用图像分析仪,扫描电子显微镜(SEM),能量色散光谱仪(EDS)和X射线衍射仪等仪器,对冲击韧性和耐磨损性能进行了测试,还对断口和磨损表面进行了研究。结果表明,对于过共晶(白口)铸铁,凝固过程中的微观组织控制是取得冲击韧性和耐磨性之间的最佳组合的最重要手段。在提高冲击韧性和耐磨性上,添加铌和动态凝固综合作用比每个单一因素更有效。在铸态条件下,动态凝固的冲击韧性和耐磨性比静态凝固分别提高71.4%和10%。加入2%铌后,分别进一步提高到114.3%和28.8%。较低的回火温度260℃比亚临界回火温度500℃显示出更好的耐冲击性和耐磨性。This study aimed at optimizing impact toughness and abrasion wear resistance of 15%Cr-2%Mo hypereutectic abrasion-resistant white irons.The effects of dynamic solidification,niobium addition,combined action of them and heat treatment have been investigated.Investigations were performed by means of the image analyzer,scanning electron microscopy（SEM）,energydispersive spectrometry（EDS）and X-ray diffraction.Impact toughness and abrasion wear resistance tests were conducted.Fracture and worn surfaces were studied.Results indicat that microstructural control during solidification is the most valuable tool to attain the optimum combination between impact toughness and wear resistance in hypereutectic iron.Combined action of Nb addition and dynamic solidification improves impact toughness and wear resistance even more than the action of each individual factor.In the as-cast condition,impact toughness and abrasion resistance were improved after dynamic solidification compared to statically solidified one by 71.4% and 10% respectively.This enhancement was increased to 114.3% and 28.8% by adding 2% Nb.Lower tempering temperature of 260 ℃ exhibits better impact and abrasion resistance than the sub-critical tempering temperature of 500 ℃.

关 键 词：过共晶铬钼白口铸铁 动态凝固 铌 综合作用 热处理 冲击韧性 断口学 耐磨性 磨损表面 

分 类 号：TG252[金属学及工艺—铸造]