Influence of All-Round Forging under Short-Term Creep Conditions on the Structure and Mechanical Properties of the Al7075/10SiCp Composite with an Aluminum Matrix

The effect of the preliminary deformation and heat treatment by all-round forging under conditions of short-term high-temperature creep on the microstructure and mechanical properties of a composite material based on a high-strength aluminum alloy of the Al–Cu–Mg–Zn system (Al7075) strengthened with SiC particles (10 wt %) is investigated. The most effective regime of short-term high-temperature creep is established experimentally. It is found that an avalanche-like increase in the rate of relative deformation occurs upon heating to temperatures above 500°C. This increase is due to the local appearance of a liquid phase at the boundaries between the needle-like particles of the S-phase and an Al based solid solution in the composite matrix in accordance with the eutectic transformation α-Al + S(Al₂CuMg) → L. After deformation and heat treatment, reinforcing SiC particles are redistributed and the structure of the composite is transformed from a cellular to a uniform configuration. At the same time, the micromechanical properties are leveled over the volume of the composite. The maximum value of the resistance to deformation in the axial compression test increases.