Mechanical properties structural sensitivity of Al—Mg—Si ternary system cast aluminum alloys at elevated temperatures

Abstract

Comparative analysis of two cast aluminum alloys mechanical properties, the structure of which differed by presence or absence of eutectic component, was carried out by standard mechanical tensile tests at temperatures of 20—500 °С and by the method of stress surges. Three temperature ranges, in which different mechanisms of hardening were realized, were established during uniaxial tensile tests. According to stress surges method, tests were carried out in the temperature range of 200—400 °С at a step strain rate change from 10^-2 to 10^-6 с^-1. The temperature-speed intervals, in which one of the selected alloys is preferred by its creep resistance, were defined. It is eutectic alloy at low temperatures and high rate strain, and dispersion-hardening solid solution at high temperatures and low strain rates. Full text download