Method for preparing Mg-Ti-B grain refiner for magnesium and magnesium alloy

Abstract

The invention provides a method for preparing a grain refiner for magnesium and magnesium alloy. The chemical compositions of the refiner are as follows (by weight percent): 13.78-55.10% of titanium, 6.22-24.90% of boron and the balance of magnesium. The preparation method comprises the following steps: titanium powder, boron powder and magnesium powders are mixed in a drying status, compacted and dried and then are arranged in a corundum crucible; the crucible is landfilled with fire-resisting powder; an isothermal treatment is carried out at the temperature of 700 to 1000 DEG C in a box-type resistance furnace for 60 to 180 min to prepare the Mg-TiB2 grain refiner. The method is simple in preparation procedure, easy in controlling the content of TiB2 and adding the TiB2, and capable of prominently refining the grain of the magnesium and magnesium alloy.

Description

technical field

[0001] The invention relates to the field of metal materials, in particular to a method for preparing a grain refiner for magnesium and magnesium alloys. The prepared grain refiner can effectively refine the grains of magnesium and magnesium alloys. Background technique

[0002] The industrial application of magnesium alloys began in the 1930s. At present, magnesium alloys have been widely used in the transportation industry and 3C electronic products and other fields, and the global magnesium consumption is growing rapidly at a rate of 20% per year, which is unprecedented in the application of modern engineering metal materials. Therefore, magnesium alloys are known as It is the green engineering material with the most development and application potential in the 21st century. However, magnesium alloy has a close-packed hexagonal crystal structure with few slip systems, which makes it difficult to plastically deform. In addition, the surface of magnesium a...

Examples

example 1

[0036] Example 1: Mg-80%TiB 2 Preparation of grain refiner

[0037] (1) Dry mix 55.10% titanium powder, 24.90% boron powder and 20% magnesium powder on a mixer for 12 hours by weight, then cold press into a prefabricated block with a relative density of 45%, wrap it with aluminum foil and dry it processed and buried in corundum crucibles;

[0038] (2) Use a box-type resistance furnace for isothermal treatment at 900°C for 100 minutes;

[0039] (3) Take out the prefabricated block to make Mg-80%TiB 2 grain refiner;

[0040] (4) After adding 0.5% of the grain refiner to the AZ91D magnesium alloy, the grain size of the alloy can be reduced from 96 μm to 53 μm.

example 2

[0041] Example 2: Mg-50%TiB 2 Preparation of grain refiner

[0042] (1) Dry mix 34.44% titanium powder, 15.56% boron powder and 50% magnesium powder on a mixer for 10 hours by weight, then cold press into a prefabricated block with a relative density of 50%, wrap it with aluminum foil Dried and buried in a corundum crucible;

[0043] (2) Use a box-type resistance furnace for isothermal treatment, and hold at 800°C for 120min;

[0044] (3) Take out the prefabricated block to make Mg-50%TiB 2 grain refiner;

[0045] After adding 1.4% of the grain refiner to the AZ91D magnesium alloy, the grain size of the alloy can be reduced from 96 μm to 58 μm.

example 3

[0046] Example 3: Mg-20%TiB 2 Preparation of grain refiner

[0047] (1) The titanium powder that is 13.78% by weight, the boron powder of 6.22% and the magnesium powder of 80% are cold-pressed into the prefabricated block of relative density 48% after 8 hours on the mixer, dry after wrapping with aluminum foil processed and buried in corundum crucibles;

[0048] (2) Isothermal treatment at 850°C for 180min in a box-type resistance furnace;

[0049] (3) Take out the prefabricated block to make Mg-20%TiB 2 grain refiner;

[0050] After adding 1.5% of the grain refiner to the AZ91D magnesium alloy, the grain size of the alloy can be reduced from 96 μm to 56 μm.

technical field

[0001] The invention relates to the field of metal materials, in particular to a method for preparing a grain refiner for magnesium and magnesium alloys. The prepared grain refiner can effectively refine the grains of magnesium and magnesium alloys. Background technique

[0002] The industrial application of magnesium alloys began in the 1930s. At present, magnesium alloys have been widely used in the transportation industry and 3C electronic products and other fields, and the global magnesium consumption is growing rapidly at a rate of 20% per year, which is unprecedented in the application of modern engineering metal materials. Therefore, magnesium alloys are known as It is the green engineering material with the most development and application potential in the 21st century. However, magnesium alloy has a close-packed hexagonal crystal structure with few slip systems, which makes it difficult to plastically deform. In addition, the surface of magnesium a...

Examples

example 1

[0036] Example 1: Mg-80%TiB 2 Preparation of grain refiner

[0037] (1) Dry mix 55.10% titanium powder, 24.90% boron powder and 20% magnesium powder on a mixer for 12 hours by weight, then cold press into a prefabricated block with a relative density of 45%, wrap it with aluminum foil and dry it processed and buried in corundum crucibles;

[0038] (2) Use a box-type resistance furnace for isothermal treatment at 900°C for 100 minutes;

[0039] (3) Take out the prefabricated block to make Mg-80%TiB 2 grain refiner;

[0040] (4) After adding 0.5% of the grain refiner to the AZ91D magnesium alloy, the grain size of the alloy can be reduced from 96 μm to 53 μm.

example 2

[0041] Example 2: Mg-50%TiB 2 Preparation of grain refiner

[0042] (1) Dry mix 34.44% titanium powder, 15.56% boron powder and 50% magnesium powder on a mixer for 10 hours by weight, then cold press into a prefabricated block with a relative density of 50%, wrap it with aluminum foil Dried and buried in a corundum crucible;

[0043] (2) Use a box-type resistance furnace for isothermal treatment, and hold at 800°C for 120min;

[0044] (3) Take out the prefabricated block to make Mg-50%TiB 2 grain refiner;

[0045] After adding 1.4% of the grain refiner to the AZ91D magnesium alloy, the grain size of the alloy can be reduced from 96 μm to 58 μm.

example 3

[0046] Example 3: Mg-20%TiB 2 Preparation of grain refiner

[0047] (1) The titanium powder that is 13.78% by weight, the boron powder of 6.22% and the magnesium powder of 80% are cold-pressed into the prefabricated block of relative density 48% after 8 hours on the mixer, dry after wrapping with aluminum foil processed and buried in corundum crucibles;

[0048] (2) Isothermal treatment at 850°C for 180min in a box-type resistance furnace;

[0049] (3) Take out the prefabricated block to make Mg-20%TiB 2 grain refiner;

[0050] After adding 1.5% of the grain refiner to the AZ91D magnesium alloy, the grain size of the alloy can be reduced from 96 μm to 56 μm.

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