铝青铜表面激光熔覆层组织与性能研究  

Microstructure and Performance of Laser Cladding on Surface of Aluminum Bronze

作　　者：徐建林[1,2] 杨波 高威[4] 王智平[1,2] 龙大伟[1,2] 居春艳[1,2] 于涛[1,2] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,兰州730050 [2]兰州理工大学有色金属合金及加工教育部重点实验室,兰州730050 [3]中国第二重型集团公司重型压力容器与核电技术研究所,四川德阳618000 [4]北京航空材料研究院,北京100095

出　　处：《航空材料学报》2009年第1期63-67,共5页Journal of Aeronautical Materials

基　　金：兰州理工大学博士基金项目(SB01200608)

摘　　要：采用激光熔覆技术在QAl9-4铝青铜表面熔覆了一层Ni基合金层,以提高QAl9-4铝青铜的耐磨性。为了提高QAl9-4铝青铜对激光的吸收率,实验采用少量自制的粘结剂并配合压力机将合金粉末预置在QAl9-4铝青铜表面,然后激光重熔。通过对QAl9-4铝青铜表面熔覆层组织研究分析表明:熔覆层与基体形成了良好的冶金结合,无裂纹缺陷的存在;熔覆层组织受凝固速度的影响较大,其表面组织为胞状晶,中部为发达的树枝晶,结合区上部由于基体的激冷作用而呈细晶区,细晶区以下又以树枝晶和胞状晶为主。激光熔覆层的平均硬度是QAl9-4铝青铜基体硬度的3倍多。A Ni matrix alloy cladding was deposited on the surface of QA19-4 aluminum bronze by laser remelted technology to improve its wear resistance. In order to improve absorptivity of aluminum bronze for laser irradiation, some alloy powders were pre-deposited on the surface of QA19-4 aluminum bronze by compressive equipment and some binder, which was developed by researcher. Then, these alloy powders were remehed by laser. The analysis of the laser cladding on the surface of QA19-4 aluminum bronze shows that the composite region of remelted cladding and QA19-4 aluminum bronze is a better metallurgical bond and there aren＇ t cracks. The microstructure of cladding is affected by solidification rate. The microstructure of the cladding＇ s surface is cellulated crystal. In the middle part of the cladding, the microstructure is dendritic crystal. Because of chilling effect of QA19-4 aluminum bronze, the microstructure of the composite region upper is fine grain band. The microstructure of the composite region lower is cellulated crystal and dendritic crystal. The average Vickers hardness of the cladding is three times as hard as that of ordinary QA19-4 aluminum bronze.

关 键 词：铝青铜 激光熔覆 表面改性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]