Effect of Thermodeformation Treatment on the Structure and Mechanical Properties of the Al3Ca1Cu1.5Mn Alloy

The processability of the Al3Ca1Cu1.5Mn alloy in the course of thermodeformation treatment has been studied. Its structure has been analyzed in cast and deformed states. The cast structure is composed of primary Al crystals and ultrafine eutectic colonies formed by (Al) and submicron Al₄Ca intermetallide particles with revealed solubility of copper and manganese in both structural components. An essential reduction in size to 300–500 nm has been revealed in the process of deformation for eutectic intermetallides which are uniformly distributed over the composite material volume. Rolled sheets demonstrate a high stability of their properties in the course of thermal treatment at 250 and 350°C. In particular, it has been found that the annealing of a hot-rolled sheet of 0.5 mm in thickness at 250°C for 12 h decreases the alloy microhardness by only ~5%. The most advantageous regimes of the production of rolled sheets provide the balanced mechanical properties, when the ultimate strength is 220–230 MPa, and the ultimate yield strength is 190–200 MPa at a relatively high elongation of 9%.