Conductive aluminum alloy section bar formula of subway locomotive and preparation method thereof

Abstract

The invention belongs to the field of metal materials and particularly relates to a conductive aluminum alloy section bar formula and a preparation method thereof. The aluminum section bar formula is prepared from the following element components in percentage by weight: 0.45%-0.5% of Si, 0.5%-0.65% of Mg, 0.1%-0.25% of Fe, not greater than 0.03% of Mn, not greater than 0.03% of Cr, not greater than 0.05% of Cu, not greater than 0.05% of Zn, not greater than 0.05% of Ti, not greater than 0.03% of other single impurity, not greater than 0.1% of other impurities, and the balance of Al, based on 100% in total. The preparation method of the conductive aluminum alloy section bar formula comprises steps of casting, homogenizing, cast ingot heating, extruding and thermal processing, wherein the thermal processing step adopts double-stage manual ageing thermal treatment, and the ageing condition is T6 + (210+ / -5 DEG C, 2h). The aluminum alloy magnesium silicide manufactured by the conductive aluminum alloy section bar formula disclosed by the invention is uniform in strengthening phase diffusion, and has good strength and inter-crystalline corrosion resistance.

Description

【Technical field】 [0001] The invention belongs to the field of metal materials, and in particular relates to a formula of a conductive aluminum alloy profile for a subway locomotive and a preparation process thereof. 【Background technique】 [0002] At present, the bus bar of the overhead rigid suspension system of domestic urban rail transit is generally made of aluminum alloy profiles. The main function of the bus bar is to conduct current and clamp the contact wire. Therefore, there are certain requirements for the conductivity and mechanical properties of aluminum alloy. Achieving tensile strength ≥ 215MPa, yield strength ≥ 160MPa, elongation ≥ 8%, volume resistivity < 0.0329Ω.mm at 20°C 2 / m (equivalent to a volume conductivity IACS of 52.5%). As we all know, the higher the purity of the aluminum alloy, the better the electrical conductivity, but the lower the mechanical properties. Therefore, there is a contradiction between improving the electrical conductivity o...

AI Technical Summary

Problems solved by technology

The main reason is that the heat treatment strengthening phase is an impurity phase formed by magnesium silicide, excess silicon and impurity iron. When the amount of silicon is large, it not only reduces the plasticity of the material, but also reduces the electrical conductivity.