汽车用镁合金激光表面熔覆Al-Si合金涂层组织和性能研究  

Microstructure and Properties of Al-Si Alloy Coating on Magnesium Alloy by Laser Cladding

作　　者：刘莹莹[1] 赵强强[2] 

机构地区：[1]内蒙古交通职业技术学院,内蒙古赤峰024005 [2]河北工业大学材料科学与工程学院,天津300401

出　　处：《铸造技术》2016年第12期2591-2593,共3页Foundry Technology

摘　　要：采用激光熔覆技术在汽车用镁合金表面制备Al-Si合金涂层,对Al-Si合金涂层的组织和性能进行研究。结果表明,Al-Si合金熔覆层组织主要为树枝晶,主要物相为Mg_2Al_3、Mg_(17)Al_(12)、Mg_2Si。镁合金激光表面熔覆Al-Si合金涂层硬度分为4个不同区域,分别为熔覆层、结合区、热影响区和镁基体,其中次表层硬度最高,基体层硬度最低。镁合金表面随着激光功率的增加,熔覆层耐磨性和耐腐蚀性能提高。随着激光功率的增加,耐磨性先增加后降低,耐蚀性逐渐提高。Al-Si alloy coating was prepared on the surface of magnesium alloy by laser cladding, and the microstructure and properties of the Al-Si alloy coating were studied. The results show that the microstructure of the cladding layer is mainly dendrite, and the main phase is Mg2A13, Mg17Al12 and Mg2Si. The hardness of the Al-Si alloy coating on magnesium alloy can be divided into 4 different zones, which are the cladding layer, the bonding zone, the heat affected zone and the magnesium matrix. The hardness of sub surface is the highest and that of the matrix layer is the lowest. The wear resistance and corrosion resistance of the cladding layer increase with the increase of laser power. With the increase of laser power, the wear resistance increases at first and then decreases, and the corrosion resistance increases gradually.

关 键 词：镁合金 激光熔覆 显微组织 腐蚀速率 

分 类 号：TG174.4[金属学及工艺—金属表面处理]