Mg Alloys Containing Misch Metal Manufacturing Method of Wrought Mg Alloys Containing Misch Metal, and Wrought Mg Alloys Thereby

Abstract

There are provided a magnesium alloy with a misch metal, a method of producing a wrought magnesium alloy with a misch metal, and a wrought magnesium alloy produced thereby, in which a great deal of misch metal is added to magnesium, and thus refractory eutectic phases or multi-phases are formed into a stable network structure or a stable dispersed phase, thereby inhibiting deformation of a magnesium matrix at a high temperature to maintain a high strength. The magnesium alloy with the misch metal has the formula of Mg100-x-y-gAxByCz, where A is zinc (Zn) or aluminum (Al); B is the misch metal; C is at least one element selected from the group consisting of manganese (Mn), nickel (Ni), copper (Cu), tin (Sn), yttrium (Y), phosphor (P), silver (Ag), and strontium (Sr); and x, y and z are the compositions of 0 at %≦x≦6 at %, 0.8 at %≦y≦7 at %, and 0 at %≦z≦2 at %, respectively.

Description

DESCRIPTION [0001]1. Technical Field[0002]The present invention relates to a magnesium alloy with a misch metal, in which a great deal of misch metal is added to magnesium, thereby having a network structure or a dispersed phase which is stable at a high temperature and thus exhibiting excellent mechanical properties. Further, the present invention relates to a method of producing a wrought magnesium alloy which granulates solidification structures, i.e. secondary phases or multi-phases, by means of hot extrusion and hot rolling, and ultra-refines grains of a matrix, and a wrought magnesium alloy produced by the method.[0003]2. Background Art[0004]Nowadays, as environmental and saveenergy problems attract a lot of attention all over the world, it is absolutely required to make parts lighter in weight. There are stronger and stronger requests that an environmental pollution problem resulting from carbon dioxide generated during transportation by road, aviation, and rail should be sol...

AI Technical Summary

Benefits of technology

"The present invention provides a magnesium alloy with a misch metal that can form a stable network structure or a stable dispersed phase, which prevents deformation of the magnesium matrix at high temperatures. The addition of other elements to the alloy strengthens the matrix structure or solid-solution limit, resulting in improved mechanical properties at room temperature. The method of producing the alloy involves fusion-casting the alloy composition, hot-extruding it, and refining grains through granulation and dispersion of other phases than magnesium in the cast, and recrystallization of a matrix. The resulting alloy has fine grain structure and excellent mechanical properties, such as high strength and high toughness."

Problems solved by technology

In the casting magnesium alloy, because a molten metal frequently generates an eddy when passing through the gate of a metal mold to enter a cavity, its product contains a number of blowholes.

These remaining blowholes results in generating a blister on a surface of the product during heat treatment including solution heat treatment in the future, the product is not typically subjected to the heat treatment.

Hence, the AZ91 alloy has a difficulty in being applied to parts exposed to a high temperature (150° C. or more) such as a transmission case of an automobile.

However, so far, there is a limit to utility in the aspects of productivity, mechanical properties including the high-temperature creep property and corrosion resistance, and costs.

Thus, these elements have been restrictively used for the case of giving a greater weight on performance than a cost.

Meanwhile, conventionally, there is a technical problem on formation of the magnesium alloy.

For this reason, it is very difficult to form a product at a room temperature.

However, the magnesium alloy plate having a required fine grain structure is not efficiently produced using a currently commercialized magnesium alloy.

In this case, the reduction in thickness is restricted due to serious cracking, and thus the grain refinement is restricted.

In other words, this solid solution alloy is restricted in a source capable of generating recrystallization in its interior, and thus has a limit to the grain refinement.

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