扫描速度对球墨铸铁表面等离子束硬化组织和性能的影响  

Influence of Scanning Speed on Plasma Beam Remelt-solidified Layer's Microstructure and Performance of Nodular Cast Iron

作　　者：张娜[1] 刘政 李刚[1] 

机构地区：[1]华北水利水电学院,河南郑州450011 [2]徐州工程机械科技股份有限公司,江苏徐州221004

出　　处：《铸造技术》2010年第2期143-145,共3页Foundry Technology

摘　　要：对不同扫描速度下球墨铸铁表面等离子束处理的组织和性能进行了分析研究。结果表明,在保持工作电流为60 A,工作电压为30 V的条件下,扫描速度从10 mm/s增加到50 mm/s,球墨铸铁表面发生了熔凝硬化;扫描速度增大,熔凝层和硬化层的深度、宽度减小,硬化层的最高硬度值增大,熔凝硬化区石墨相消失,其室温组织为细小的变态莱氏体+残余奥氏体,相变淬火区组织为针状马氏体+变态莱氏体+包围球状石墨的变态莱氏体、马氏体双壳组织;双壳组织硬度达到917.8HV0.1,对提高耐磨性有利。Microstructure and performance of plasma beam remelt-solidified layer of nodular cast iron surface under different scanning speeds have been analyzed. The results show that micromeltedsolidified hardening of the nodular cast iron surface can be obtained when the working current is 60 A and the welding voltage is 30 V, whereas the scanning speed increases from 10 mm/s to 50 mm/s. Along with the scanning speed increasing, the width and depth of remelt-solidified layer and hardened layer diminishes, and maximum hardness increases. In remelt-solidified region graphite vanished and the microstructure at room temperature is tiny modified ledeburite and remaining austenite. In transformation hardening region is acicular martensite, modified ledeburite and double shell structure consists of modified ledeburite and martensite, in the center of shell is nodular graphite. The microhardness of double shell structure is up to 917.8 HV0.1, Which is advantageous to enhance wear resistance.

关 键 词：球墨铸铁 等离子束 熔凝硬化 耐磨性 

分 类 号：TG143.5[一般工业技术—材料科学与工程]