Determination of the Effect of Cold Working Compression on Residual Stress Reduction in Quenched Aluminium Alloy 2219 Block

Abstract

Residual stresses are locked-in stresses that remain in solid materials after the removal of the external cause of stresses [1]. Residual stresses are induced in components during most manufacturing processes, such as material deformation, heat treatment, machining, or processing operations that transform the shape or change the properties of the material [1]. They develop when a body undergoes inhomogeneous plastic deformation or is exposed to a non-uniform temperature distribution, such as in the case of welding, warm forming, casting, and quenching processes [2] to [4]. A material’s ability to resist fatigue, and crack initiation and propagation at ambient temperature, brittle fracture, machining distortion, and corrosion cracking is adversely affected by residual stresses [3] and [5] to [7]. These effects regularly cause significant costs of repairs or replacement of parts [5]. Analysis of residual stresses is considered as one of the necessary steps in the design of structural elements and components, which aid in predicting their reliability under different loading conditions during operation [6]. Extensive studies revealed that the fatigue strength of welded elements is drastically reduced due to high residual stresses induced at the weld bead and heat-affected zone (HAZ) [8] and [9]. Webster et al. reported that residual stress, which can be in excess of the yield strength of the material, could develop at the HAZ: is the region near the weld zone that is not melted during welding, but its properties have been severely altered due to the effect of the welding torch [10] to [12]. Therefore, the effects of residual stresses are comparably the same as that of stress concentration. Residual stresses are now considered one of the leading factors influencing the properties of metallic materials. Thus, they should be given due consideration during the design and manufacturing of parts and components. Due to their self-equilibrating nature, the presence of residual stresses may not be readily evident, and so they may not be carefully considered during engineering design. However, they are stresses and must be given due consideration in the same way as stresses due to external loading. The hole-drilling technique based on ASTM E-837-13a standard [13] is used to measure the residual stresses, as presented in this paper; the residual stresses cannot be measured directly [14]. Usually, the elastic strains resulting from the relieved stresses initially present at hole position are measured directly, then, the residual stresses can be computed using mathematical relations. Determination of the Effect of Cold Working Compression on Residual Stress Reduction in Quenched Aluminium Alloy 2219 Block Ahmad, A.S. – Yunxin, W. – Hai, G. – Lei, L. Abdulrahaman Shuaibu Ahmad1,2 – Wu Yunxin1,2,* – Gong Hai1,2 – Liu Lei2 1Central South University, College of Mechanical and Electrical Engineering, China 2Central South University, State Key Laboratory of High-Performance Complex Manufacturing, China