Low-cost high-strength high-ductility rare earth magnesium alloy and preparation method thereof

Abstract

The invention discloses a low-cost high-strength high-ductility rare earth magnesium alloy and a preparation method thereof. The magnesium alloy comprises the following specific components including, by weight, 0.1 to 6.0 percent of Y, 0.1 to 6.0 percent of Gd, 0.1 to 6.0 percent of Sm, 0.01 to 2.0 percent of Zn, 0.01 to 2.0 percent of Sn, 0.01 to 2.0 percent of Bi, 0.01 to 1.0 percent of Sb, 0.1 to 1.0 percent of Zr and the balance Mg and inevitable impurities, wherein the impurity content is less than or equal to 0.1 percent by weight. According to the low-cost high-strength high-ductility rare earth magnesium alloy and the preparation method, by reasonably controlling the contents of cheap rare earth elements including Sm, Y and Gd and non-rare earth elements including Zn, Sn, Bi and Sb in the alloy, precipitation of a magnesium rare earth strengthening phase is promoted, a brand new non-basal precipitated phase and a non-rare earth precipitated phase are formed, and the rare earth content is reduced; and a new process combining high-temperature low-speed extrusion cogging and variable-temperature variable-speed rolling is adopted, grains and a second phase are further refined, and the high-strength and high-ductility rare earth magnesium alloy with the flat and smooth alloy surface is prepared. At the normal temperature, the alloy tensile strength of an alloy plate prepared through the method is larger than or equal to 515 MPa, the yield strength is larger than or equal to 450 MPa, and the ductility is larger than or equal to 10%; and the tensile strength of the alloy at the high temperature of 200 DEG C is larger than or equal to 501 MPa, the yield strength is larger than or equal to 430 MPa, and the ductility is larger than or equal to 12%.

Description

technical field [0001] The invention relates to the technical field of rare-earth magnesium alloys, in particular to a low-cost, high-strength and high-ductility rare-earth magnesium alloy and a preparation method thereof. Background technique [0002] Magnesium alloy is currently the lightest metal structure material in engineering applications, with a density of 1.8g / cm 3 About one quarter of the density of steel, with light weight, high specific strength, good shock absorption, good casting performance, good cutting performance and damping performance, good anti-electromagnetic wave interference performance, good recyclability and other excellent properties , known as "21st Century Green Engineering Materials", has been widely used in automobiles, motorcycles, 3C products (computers, communications, consumer electronics), aerospace, new energy, mechanical equipment and other fields. [0003] Compared with cast magnesium alloys, wrought magnesium alloys have a finer struc...

AI Technical Summary

Problems solved by technology

However, the content of rare earth elements in GW series alloys is relatively high (RE>10%), and the cost of use is relatively high