Effects of pressure,die, and stress-relief temperatures on the residual stresses and mechanical properties of squeeze-cast aluminum rods

The effects of die heating and stress-relief temperatures in reducing residual stresses of squeeze-cast aluminum alloy rods are experimentally determined by the longitudinal slitting method, and their reduction effects on the mechanical properties of the squeeze-cast alloy rods are investigated. Stress relief is much more effective than die heating in reducing residual stresses of the squeeze-cast alloy. Stress relief is substantially completed at 350 ° in 1 h, but at the expense of reduction in strength and hardness. Appreciable reduction in strength and hardness is avoided by using a stress-relief temperature of 250 ° for residual stress reduction of squeeze-cast aluminum alloy. Die heating to a maximum of 200 ° is considered adequate to substantially reduce the chilling effect of the metal mold on the solidifying molten metal and to avoid appreciable reduction of strength and hardness resulting from die heating effects.