Effect of grain refinement on mechanical and corrosion behavior of AZ91 magnesium alloy processed by ECAE

7th Modern Technologies in Industrial Engineering

工业技术（总论）

Gajanan, M.N.^1 ; Narendranath, S.^1 ; Satheesh Kumar, S.S.^2

NITK, Determent of Mechanical Engineering, Surathkal Mangalore

575025, India^1

Near Net Shape Group, DMRL, Kanchanbagh Hyderabad

500058, India^2

关键词: AZ91 magnesium alloys;    Corrosion behavior;    Dislocation densities;    Electrochemical polarization test;    Equal channel angular extrusion;    Fine grain structure;    Micro-structural observations;    Secondary phase particles;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/591/1/012015/pdf
DOI  :  10.1088/1757-899X/591/1/012015

学科分类：工业工程学

来源: IOP

【 摘 要 】

AZ91 Mg alloys were processed by equal channel angular extrusion (ECAE) up to 4 passes through route-R. The increase in number of ECAE passes to yield fine-grain structure in the bulk Mg alloy with a more dislocation density, this enhances mechanical properties and corrosion resistance. Indeed, microstructural observations revealed an equiaxed and significant grain refinement after ECAE-4P, with a mean grain size (d) of ∼ 4.36μm. Further, the tensile strength, micro-hardness and corrosion resistance were also increased, however the elongation was reduced with the increasing of ECAE passes. The electrochemical polarization test in 3.5wt % NaCl solution revealed a noticeable enhancement in the corrosion resistance of ECAE processed AZ91 Mg alloy compared with the as-received Mg alloy. This is mainly due to grain refinement and distribution of secondary phase particles in Mg alloy matrix during ECAE-4P.