Al-42Si aluminum alloy with room-temperature compression superplasticity and preparation process thereof

Abstract

The invention discloses an Al-42Si alloy with room-temperature compression superplasticity and a preparation process thereof. According to the aluminum alloy, a non-self-consumption vacuum arc furnace is adopted for melting Al-42Si aluminum alloy ingots in the vacuum environment, aluminum alloy melt is adsorbed into a water-cooling copper mould through a vacuum adsorption casting method to be prepared into a rod-shaped Al-42Si sample with the diameter being 5 mm, and then the Al-42Si sample is subjected to heat treatment. According to preparation of the Al-42Si alloy sample, a proper quantity of Al-42Si aluminum alloy ingots are placed in a copper crucible of the non-self-consumption vacuum arc furnace, then a furnace cavity is vacuumized to 1*10<-4> Pa, the furnace cavity is filled with high-purity argon so that the pressure in the furnace cavity can reach 40 Pa, then the Al-42Si alloy is molten, and the alloy melt is adsorbed into the water-cooling copper mould. According to the heat treatment process of the Al-42Si alloy, the rod-shaped Al-42Si sample is placed in a vacuum heat treatment furnace to be subjected to heat preservation for 6 h at the temperature being 480 DEG C for water quenching, and then furnace cooling is carried out till the room temperature is achieved after heat preservation is carried out for 8 h at the temperature being 240 DEG C. The aluminum-silicon alloy is prepared from, by weight, 42% of Si and the balance Al, the yield strength of the aluminum-silicon alloy is 300 MPa, the hardness of the aluminum-silicon alloy is 39.0 HBW, the electrical resistivity of the aluminum-silicon alloy is 0.083 microohm m, and the aluminum-silicon alloy has room-temperature compression superplasticity.

Description

technical field [0001] The invention relates to a room temperature compression superplastic Al-42Si aluminum alloy and a preparation process thereof. Background technique [0002] Due to its high specific strength and hardness, low density, strong corrosion resistance and wear resistance, good high temperature performance, small linear expansion coefficient, strong thermal conductivity, and low cost, high-silicon Al-Si alloys are ideal for engine pistons, precision wear-resistant parts and Ideal material for electronic packages. However, high-silicon aluminum alloys exhibit brittleness due to coarse primary silicon, resulting in poor processing and forming properties, which greatly limits their industrial applications. Through rapid solidification and heat treatment, the morphology and distribution of phases in high-silicon aluminum alloys can be improved, and various properties of high-silicon aluminum alloys can be improved. Therefore, it is of great significance to prep...

AI Technical Summary

Problems solved by technology

However, high-silicon aluminum alloys show brittleness due to coarse primary silicon, resulting in poor processing and forming properties, which greatly limits their industrial applications.