激光原位合成NiAl与Ni3Al金属间化合物涂层研究  

Preparing of NiAl and Ni3Al Intermetallic Composite Coatings by Laser Cladding In Situ Synthesis

作　　者：程广萍[1] 

机构地区：[1]安徽工业大学材料科学与工程学院,马鞍山243002

出　　处：《金属材料研究》2011年第2期1-5,共5页Research on Metallic Materials

基　　金：安徽省中韩国际科技合作计划（08080703020）

摘　　要：采用激光熔覆技术，利用镍包铝、镍基合金与铝的混合粉，在钢基底上原位合成了NiAl，Ni3Al金属间化合物覆层。实验结果表明，镍包铝中添加镍基合金与铝后，由于镍基合金的自熔性效果以及镍与铝之间的反应放热，熔覆功率得以降低，不仅改善了熔覆质量，同时降低了基底中铁元素的熔化量，减轻了其对涂层的稀释作用；覆层主要由NiAl和Ni3Al两相构成，其中NiAl相呈树枝晶形貌，为主要基体相；NiAl相沿树枝晶间连续分布，数量相对较少，其中树枝晶NiAl相和枝晶间Ni3Al相的Ni，Al，Fe，Si的原子百分含量分别为54：39：2：5以及70：21：3：6；原位合成涂层的硬度达到Hv490～540。ABSTRACT Ni-A1 intermetallic compound coatings were prepared on mild st＇eel substrate by Laser-cladding in situ synthesis with mixed powders of nickel-coated aluminum, Ni-based alloy and Al. The results shown that the quality of the coating was improved comparing with cladding nickel-coated aluminum, and the dilution of iron from substrate to coating were greatly reduced, as a result of lower cladding powers due to self-fluxing of Ni-based alloy and exothermic reaction between Ni and Al. The two-phase microstructure of the coating consisted mainly of large number NiAl and fewer Ni3 Al, with NiAl being uniformity and staggered fine dendrites surrounded continuously by Ni3A1, and the atom ratio of Ni ： Al： Fe ：Si in NiAl or NiaAl is 54 ： 39 ： 2 ： 5 or 70 ： 21 ： 3 ： 6.The hardness of coatings was up to Hv490-540.

关 键 词：激光熔覆 金属间化合物 复合涂层 NI3AL 

分 类 号：TG142.45[一般工业技术—材料科学与工程]