宽带电弧熔覆层的缺陷控制  

Defects Controlling of the Lays Prepared with Broad-beam Arc Cladding Technology

作　　者：张昕[1] 姜海[1] 程华[1] 孔德新[1] 

机构地区：[1]中国人民解放军装甲兵技术学院机械系,长春130117

出　　处：《中国表面工程》2012年第1期56-59,共4页China Surface Engineering

摘　　要：宽带电弧熔覆技术修复零部件,不可避免会产生裂纹,使修复部位的承载能力下降。为避免修复缺陷的产生,文中分析了熔覆裂纹产生的原因,采用38CrSi为基体材料,在熔覆材料Ni-Cr-B-WC中添加5%～8%的稀土元素Re,进行单道送粉熔覆。利用扫描电子显微镜(SEM)、硬度仪和显微硬度测试仪分别对获得的熔覆层进行显微组织观察、硬度及耐磨性等进行分析研究。结果表明,加入稀土元素后,可以细化熔覆层晶粒,柱状晶的产生范围减小,硬度增大,耐磨性提高近1倍。稀土元素的加入可以使熔覆层强韧性提高,脆性下降,减少裂纹倾向。It is inevitable that the cracks would exist in the parts repaired with broad-beam arc cladding tech- nology, which would make the cladding layers enduring ability decreased. In this paper, the terms attributing to the cracks were analyzed to avoid defects. Single pass powder feeding cladding was carried out, in which the substrate was 38CrSi and 5M-8% Re was added to the cladding material Ni-Cr-B-WC. In order to study the microstructure, hardness, and wear resistance of the cladding layers, scanning electron microscope （SEM）, hardness instrument, and microhardness tester were utilized. The results indicate that, with the ad- dition of the rare earth elements, the grains could be refined and the range of the columnar crystal would be obviously decreased. Consequently, the hardness of the layers could be improved and the wear resistance in- crease about 1 time. Furthermore, the layers＇ strength-toughness would be improved, in contrast to a de- creased brittleness, thus the cracking tendency of the layers would be decreased effectively.

关 键 词：宽带电弧熔覆 熔覆裂纹 稀土元素 

分 类 号：TG174.4[金属学及工艺—金属表面处理]