AZ91 D镁合金表面熔盐热扩渗试验  

Study on the Molten Salt Thermal Diffusion of AZ91D Magnesium Alloy

作　　者：艾小玲[1] 刘波[2] 刘生发[2] 

机构地区：[1]武汉职业技术学院 [2]武汉职业技术学院机电工程学院,武汉430074

出　　处：《特种铸造及有色合金》2015年第5期529-532,共4页Special Casting & Nonferrous Alloys

摘　　要：采用扫描电镜、能谱分析和X射线衍射,研究了ZnCl2-NaCl低温熔盐体系对AZ91D合金表面热扩渗处理的渗层组织结构的影响,并利用极化曲线分析了渗层对合金腐蚀性能的影响。结果表明,在热扩渗温度为325℃,扩渗时间分别为9、12和15h时,合金表面扩渗层平均厚度分别为7.7、8.4和14.7μm。扩渗时间为9、12h的渗层主要组成相为致密的φ-(Al5Mg11Zn4)和τ-Mg32(Al,Zn)49金属间化合物;扩渗15h的渗层组成相为τ-Mg32(Al,Zn)49。合金表面形成的热扩渗层明显改善了合金的耐蚀性能。With the help of scanning electron microscopy,energy spectrum analysis and X-ray diffraction, the microstructure of intermetallic compounds layer formed during AZ91D alloy surface thermal diffusion in the ZnCl2- NaCl low temperature molten salt system was observed,and effects of intermetallic com-pounds layer on the corrosion resistance of alloy were examined by using polarization curve test.Results show that at diffusion treatment temperature of 325 ℃ and diffusion treatment time of 9,12 and 15 h, respectively,the corresponding average thickness of AZ91D alloy surface thermal diffusion layer reaches 7.7、8.4 and 14.7μm,respectively.Surface diffusion layers are mainly composed ofφ-（Mg11Al5Zn4）,τ-Mg32 （Al,Zn）49 intermetallic compounds with the diffusion treatment time from 9 h to 12 h,while the diffusion treatment time is increased to 15 h,it consists ofτ-Mg32 （Al,Zn）49 intermetallic compounds. The thermal diffusion layer of alloy surface can obviously improve the corrosion resistance of alloy.

关 键 词：AZ91D镁合金 熔盐热扩渗 金属间化合物 耐蚀性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]