Yb-containing deformation magnesium alloy and dynamic precipitation strengthening-toughening preparation thereof

Abstract

The invention discloses deformed magnesium alloy containing Yb and a dynamic separation strengthening and toughening preparation method thereof. A strengthening phase is effectively dispersed and separated out during a deformation process by selecting a special alloy element and utilizing the universal homogenization treatment and thermal squeezing technologies during the production of the deformed magnesium alloy, thereby obtaining the compound strengthening and toughening effects of deformation strengthening, refined crystalline strengthening and precipitation hardening of the deformed magnesium alloy; the obtained high intensity deformed magnesium alloy simultaneously has the characteristics of refined crystalline strengthening, separation strengthening, intercrystalline strengthening and deformed substructure strengthening, thereby obtaining very high mechanical property; the tensile strength is larger than 380MPa; the yield strength is larger than 320MPa; and the percentage of elongation is larger than 5 percent.

Description

technical field [0001] The invention relates to the technical field of metal material strengthening and processing, in particular to a production method of a high-strength deformed magnesium alloy, in particular to a Yb-containing deformed magnesium alloy and a preparation method thereof for dynamic precipitation strengthening and toughening. Background technique [0002] Magnesium alloy is currently a lightweight metal material that is highly valued at home and abroad. It has broad application prospects in the production of automobiles, aerospace, and electromechanical and electronic products. It is an ideal lightweight substitute for steel and aluminum alloy materials. Known as "the green material of the 21st century", it is of great significance to solve or alleviate the energy crisis and environmental crisis that the world is facing now. [0003] However, due to the inherent atomic structure and crystal arrangement characteristics of magnesium alloys, their low strength ...

AI Technical Summary

Problems solved by technology

The alloying method is mainly to use various rare earth elements and Sn, Cu, Ag, etc. to alloy magnesium or to modify the existing Mg-Al and Mg-Zn series magnesium alloys, although many elements have been found to be effective on magnesium and magnesium. Alloys have a certain strengthening effect, but the strengthening effect is not significant, especially the plastic deformation ability of magnesium alloys cannot be significantly improved or even deteriorated. Therefore, special processing technologies for magnesium alloys have received extensive attention, such as ECAE and other large plastic deformation technologies. , semi-solid extrusion, reciprocating extrusion, hydrostatic extrusion, low temperature extrusion and rapid solidification-powder metallurgy-hot extrusion, etc. These methods can indeed obtain high mechanical properties and superplastic deformation capabilities, but they are all due to It is difficult to put into application due to their special manufacturing, efficiency and cost issues

[0005] The essence of the above problems is that these technical methods have the problem of single strengthening and toughening effects. For example, the alloying method pursues the second phase strengthening effect, but because no satisfactory dispersed precipitate has been found, especially after deformation processing, the fine particles are retained. The recrystallized grains are not suitable for effective subsequent heat treatment, making it difficult to fully exert the alloying effect

However, special processing technologies are mostly purely highlighting the effect of grain refinement, and it is difficult to obtain effective precipitation strengthening effects.

[0006] In fact, some scholars have recognized the significance of composite strengthening of magnesium alloys, proposed various methods to obtain composite strengthening effects through deformation heat treatment, and carried out technical attempts and principle analysis, such as liquid solution aging and solution deformation aging, etc., but none of them got rid of the limitation of the traditional deformation heat treatment technology requiring subsequent low temperature aging treatment

Then, can supersaturated alloys be used to dynamically precipitate effective dispersion strengthening phases during deformation processing, thereby completely retaining the processed state structure and simplifying the preparation technology? Scholars in the United Kingdom and Norway have tested this method in 6-series aluminum alloys in recent years, but it is realized under complex ECAE processing conditions, so it lacks practicability, and there is no similar test report on magnesium alloys so far.

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