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

• Published in: IOP conference series. Materials Science and Engineering 2018-06, Vol.376 (1), p.12045
• Main Authors: Manjunath, G K, Preetham Kumar, G V, Udaya Bhat, K
• Format: Article
• Language: English
• Subjects: Al-Zn-Mg alloy; Aluminum base alloys; Coefficients; Compression tests; Compressive strength; ECAP; Equal channel angular pressing; Flow curves; Flow properties; Grain refinement; Magnesium; Plastic deformation; Strain hardening; Stress-strain curves; True stress; Yield strength; Zinc
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/376/1/012045

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 = 120º and Ψ = 30º. 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.