Effect of homogenization treatment on microstructure and properties of Al-Mg-Mn-Sc-Zr alloy

Abstract

Abstract：The effect of homogenization on the hardness, tensile properties, electrical conductivity and microstructure of as-cast Al-6Mg-0.4Mn-0.25Sc-0.12Zr alloy was studied. The results show that during homogenization as-cast studied alloy has obviously hardening effect that is similar to aging hardening behavior in traditional Al alloys. The precipitates are mainly Al 3 (Sc,Zr) and Al 6 Mn. When homogenization temperature increases the hardness peak value is declined and the time corresponding to hardness peak value is shortened. The electrical conductivity of the alloy monotonously increases with increasing homogenization temperature and time. The decomposition of the supersaturated solid solution containing Sc and Zr which is formed during direct chilling casting and the precipitation of Al 3 (Sc, Zr) cause hardness increasing. The depletion of the matrix solid solubility decreases the ability of electron scattering in the alloy, resulting in the electrical conductivity increased. Tensile property result at hot rolling state shows that the optimal homogenization treatment processing is holding at 300−350 for ℃ 6−8 h.

Effects of Sc, Zr and Ti on the microstructure and properties of Al alloys with high Mg content

“…The improvement of hardness after addition of Sc, Zr, and Ti should due to grain refinement, the decreasing of dendrite, and dispersed secondary precipitates (Al 3 (Sc 1−x Zr x ), Al 3 (Sc 1−x Ti x ), and Al 3 (Sc 1−x−y Zr x Ti y )), which inhabit movement of dislocations. These results are consistent with Li [12] and Nie [15]. Fig.…”

Effect of Addition Zr on As-Homogenization Microstructures of 5182 Aluminum Alloy

“…Segregation and oversize intermetallic compound in as-cast microstructure of Al-Mg alloy have a great influence on the mechanical property and formability for alloys. Homogenization can eliminate the segregation and achieve homogeneous microstructure [12][13][14] . The alloys used in the experiment were heated from room temperature to 475℃ within 2.5h to avoid overheat phenomenon of some low-melting-temperature phase as shown in Fig.…”

The Phase Stability, Thermodynamics Properties and Electronic Structures of L12-Type Al3Sc and Al3Y under High Pressures

“…According to the Debye-Grüneisen model, 𝛾 and 𝐵 are constants under the same pressure, thus leading to the relationship between the thermal expansion coefficient and temperature entirely determined by the heat capacity 𝐶 𝑉 . [40] With the pressure increase, the heat capacity 𝐶 𝑉 reduces. Thus the thermal expansion coefficient decreases and tends to constant, consistent with 𝐶 𝑉 .…”