La_2O_3对铝合金表面Ni60熔覆层组织及耐蚀性的影响  

Effect of La_2O_3 on Microstructure and Corrosion Resistance of Laser Cladding Ni60 Alloys Coatings on Al Alloys

作　　者：郑英[1] 王成磊[2] 高原[2] 张光耀[2] 

机构地区：[1]湖南交通职业技术学院机电工程学院,湖南长沙410132 [2]桂林电子科技大学材料科学与工程学院,广西桂林541004

出　　处：《稀土》2014年第3期13-18,共6页Chinese Rare Earths

基　　金：国家自然科学基金青年基金项目资助(51201043);国家自然科学基金项目资助(51264007);广西自然科学基金重点项目资助(2010GXNSFD013008);广西科学研究与技术开发科技攻关计划项目资助(桂科攻12118020-2-2-1)

摘　　要：为了提高铝合金材料的表面性能,利用激光熔覆技术在6063铝合金表面制备了添加有La2O3的Ni60合金熔覆层。分析了激光熔覆La2O3+Ni60熔覆层的显微组织及硬度,研究了其耐腐蚀性能,并与Ni60合金熔覆层和铝合金基体进行了对比。结果表明,加入2%La2O3可有效地减少熔覆层中的裂纹、孔洞和夹杂物,促进晶粒细化,提高熔覆层的组织均匀性和表面硬度;在3.5%的NaCl溶液中,La2O3+Ni60熔覆层耐蚀性较未处理Al合金提高了6倍,较Ni60熔覆层提高了4.3倍;在1mol/L H2SO4溶液中,La2O3+Ni60熔覆层耐蚀性较未处理Al合金提高了19.6倍,较Ni60熔覆层提高了1.98倍;在1 mol/LNaOH溶液中,La2O3+Ni60熔覆层试样的耐蚀性较未处理的Al合金提高了99倍,较Ni60熔覆层提高了1.03倍。To improve the surface properties of aluminum alloy,La2O3＋ Ni60 alloy cladding layer metallurgically bonded to substrate was prepared on the surface of aluminum alloy by laser cladding. The microstructure and microhardness of laser cladding La2O3＋ Ni60 alloys coatings on Al alloys were investigated,its corrosion resistance was studied and discussed,a comparative study on Ni60 alloy cladding layer and aluminum alloy was made. The results show that the cracks,holes and entrapment in the coatings reduce with the addition of 2 wt% La2O3,the grain becomes small,the microstructure uniformity improves,the hardness and corrosion resistance of the coatings increase. In 3. 5% NaCl solution,the corrosion resistance of La2O3＋ Ni60 cladding layer was increased 6 times compared with untreated aluminum alloy and 4. 3 times compared with Ni60 cladding layer. In l mol /L H2SO4solution,the corrosion resistance of La2O3＋ Ni60 cladding layer was increased 19. 6 times compared with untreated aluminum alloy and 1. 98 times compared with Ni60 cladding layer. In 1 mol /L NaOH solution,the corrosion resistance of La2O3＋ Ni60 cladding layer was increased 99 times compared with untreated aluminum alloy and 1. 03 times compared with Ni60 cladding layer.

关 键 词：激光熔覆 铝合金 稀土 NI60 耐腐蚀性 

分 类 号：TG156.8[金属学及工艺—热处理]