Flow Properties of Cast Al-Zn-Mg Alloys Subjected to Equal Channel Angular Pressing

International Conference on Advances in Manufacturing, Materials and Energy Engineering 2018

材料科学;能源学

Manjunath, G.K.^1 ; Preetham Kumar, G.V.^1 ; Udaya Bhat, K.^1

Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal, Mangalore

575025, India^1

关键词: Al-Zn-Mg alloy;    ECAP;    ECAP processing;    Flow curves;    Flow properties;    Strain-hardening exponent;    Strength coefficients;    True stress strain curve;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/376/1/012045/pdf
DOI  :  10.1088/1757-899X/376/1/012045

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Flow stress can be described as the stress necessary to continue deformation at any stage of plastic strain. The strength coefficient (K) and strain-hardening exponent (n) are the two important flow properties of the material. In the present work, flow properties of three different cast Al-Zn-Mg alloys processed by equal channel angular pressing (ECAP) were investigated. ECAP processing was carried out in a die having Φ = 120° and Ψ = 30°. After ECAP processing, significant grain refinement and increase in the hardness was observed. Compression test was used to determine the flow properties of ECAP processed samples. Force-stroke data was recorded from the compression test. Flow curves were drawn by using force-stroke data. Strength coefficient and strain-hardening exponent were determined from the log-log plot of true stress-strain curves. Significant increase in the strength coefficient was observed after ECAP processing. Also, the strength coefficient is increased when the zinc content is increased in the alloy. Strain-hardening exponent was decreased with increase in the number of ECAP passes.