Microhardness Characteristics of Al-6063 Alloy Processed by Equal Channel Angular Extrusion

Abstract

In this study, annealed AL-6063 alloy was processed by the Equal Channel Angular Extrusion (ECAE) up to 6 passes at a temperature of 200°c following route A with a constant ram speed of 30 mm/min through a die angle of 90° between the die channels. The influence of ECAE processing on the evolution of microhardness in the material was studied using Vickers microhardness testing. The detailed analysis was carried out on the samples of as-received, one, two, three, four, five, and six pass conditions. The grain diameter reduced from 45μm to 2.8 μm after 6 passes of ECAE. The results indicated around 90% increase in Microhardness after 5 passes. Hardness of the inner surface where the billet was under compression was slightly higher than that of the mid-surface.

An investigation on the effects of equal channel angular pressing on the mixed‐mode fracture toughness and mechanical properties of 6063 aluminium alloy

“…The grain size of as-received and extruded materials was measured to verify the grain refinement after the ECAP process according to E112 ASTM standard. These results are compatible with the study of Nemati et al 35 The crystallite size for the extruded FIGURE 7 Scanning electron microscopy images of (A) as-received sample with ×500, (B) as-received with ×1800, and (C) after first pass with ×2000; atomic force microscope images of (D) as-received and (E) after fifth pass [Colour figure can be viewed at wileyonlinelibrary. Figure 7 shows the microstructure of as-received and extruded materials after the first pass.…”

“…Atomic force microscope images after fifth pass of the ECAP process ( Figure 7E) show grain refinement compared with the as-received material, Figure 7 D. The grain size for as-received material was measured in the range of 8 to 75 μm, and the average grain size was 45 μm. These results are compatible with the study of Nemati et al 35 The crystallite size for the extruded FIGURE 7 Scanning electron microscopy images of (A) as-received sample with ×500, (B) as-received with ×1800, and (C) after first pass with ×2000; atomic force microscope images of (D) as-received and (E) after fifth pass [Colour figure can be viewed at wileyonlinelibrary. com] materials was calculated by using X-ray diffraction profile and Williamson-Hall method.…”

“…These trends are generally consistent with earlier data where measured for the ECAPed materials. 4,34,35…”