Electron beam selective melting forming method for pure tungsten metal parts

Abstract

The invention discloses a method for electron beam selective melting and forming of pure tungsten metal parts. In the method, a three-dimensional model of the pure tungsten metal part is firstly established by software and sliced ​​to obtain slice data, and then according to the slice data of the three-dimensional model Electron beams are used to melt tungsten powder into selected areas to obtain pure tungsten metal parts. The invention uses electron beams to melt tungsten powder into shape, which improves the energy of the heat source, ensures complete melting of tungsten powder with high melting point, avoids spheroidization during the melting process of tungsten powder, and separates the forming bottom plate and tungsten powder before scanning the melting selection area. The high-temperature preheating treatment of the powder reduces the temperature gradient during the forming process of pure tungsten metal parts, slows down the cooling rate of the micro-melt pool, avoids the spheroidization of tungsten powder droplets caused by rapid cooling, and reduces the spheroidization of pure tungsten metal parts. Cracking greatly improves the forming quality of pure tungsten metal parts and increases the density of pure tungsten metal parts.

Description

technical field

[0001] The invention belongs to the technical field of material preparation, and in particular relates to an electron beam selective melting forming method for pure tungsten metal parts. Background technique

[0002] As an important metal material, tungsten has the characteristics of high melting point, high boiling point, high hardness, low expansion coefficient, low vapor pressure, etc. It is widely used in aerospace, electronics, chemical industry, nuclear industry and other fields. Due to the high melting point and low temperature brittleness of tungsten, it is difficult to prepare parts using conventional casting and machining methods. At present, most tungsten parts are prepared by powder metallurgy. The tungsten products obtained by this method have disadvantages such as low density, low strength, poor plasticity, and difficult to control impurity content, which greatly limits the application range. In addition, it is difficult to prepare tungsten par...

Examples

Embodiment 1

[0024] This embodiment includes the following steps:

[0025] Step 1. Use Pro / Engineer software to build a three-dimensional model of pure tungsten metal parts with a size of 10mm×10mm×10mm, and then use Build Assembler software to slice the three-dimensional model of pure tungsten metal parts along its height direction to obtain slice data. Then import the slice data into the electron beam selective melting forming equipment; the slice data includes contour data and graphic data of each slice section; the thickness of each layer of the slice processed by the slice is 30 μm;

[0026] Step 2: Put tungsten powder into the powder chamber of the electron beam selective melting forming equipment, and then vacuumize the forming cavity of the electron beam selective melting forming equipment to a vacuum degree of 0.5×10 -2 Pa; the shape of the tungsten powder is spherical, the mass purity is 99.95%, and the powder particle size is less than 30 μm;

[0027] Step 3, using electron bea...

Embodiment 2

[0036] This embodiment includes the following steps:

[0037] Step 1. Use Pro / Engineer software to build a three-dimensional model of pure tungsten metal parts with a size of 10mm×10mm×10mm, and then use Build Assembler software to slice the three-dimensional model of pure tungsten metal parts along its height direction to obtain slice data. Then import the slice data into the electron beam selective melting forming equipment; the slice data includes contour line data and graphic data of each slice section; the thickness of each slice processed by the slice is 100 μm;

[0038] Step 2: Put tungsten powder into the powder chamber of the electron beam selective melting forming equipment, and then vacuumize the forming cavity of the electron beam selective melting forming equipment to a vacuum degree of 1×10 -2Pa; the shape of the tungsten powder is nearly spherical, the mass purity is 99.9%, and the powder particle size is less than 100 μm;

[0039] Step 3, using electron beams ...

Embodiment 3

[0046] This embodiment includes the following steps:

[0047] Step 1. Use Pro / Engineer software to build a three-dimensional model of pure tungsten metal parts with a size of 10mm×10mm×10mm, and then use Build Assembler software to slice the three-dimensional model of pure tungsten metal parts along its height direction to obtain slice data. Then import the slice data into the electron beam selective melting forming equipment; the slice data includes contour line data and graphic data of each slice section; the thickness of each slice processed by the slice is 50 μm;

[0048] Step 2: Put tungsten powder into the powder chamber of the electron beam selective melting forming equipment, and then vacuumize the forming cavity of the electron beam selective melting forming equipment to a vacuum degree of 0.8×10 -2 Pa; the shape of the tungsten powder is spherical, the mass purity is 99.95%, and the powder particle size is less than 50 μm;

[0049] Step 3, using electron beams to pr...

technical field

[0001] The invention belongs to the technical field of material preparation, and in particular relates to an electron beam selective melting forming method for pure tungsten metal parts. Background technique

[0002] As an important metal material, tungsten has the characteristics of high melting point, high boiling point, high hardness, low expansion coefficient, low vapor pressure, etc. It is widely used in aerospace, electronics, chemical industry, nuclear industry and other fields. Due to the high melting point and low temperature brittleness of tungsten, it is difficult to prepare parts using conventional casting and machining methods. At present, most tungsten parts are prepared by powder metallurgy. The tungsten products obtained by this method have disadvantages such as low density, low strength, poor plasticity, and difficult to control impurity content, which greatly limits the application range. In addition, it is difficult to prepare tungsten par...

Examples

Embodiment 1

[0024] This embodiment includes the following steps:

[0025] Step 1. Use Pro / Engineer software to build a three-dimensional model of pure tungsten metal parts with a size of 10mm×10mm×10mm, and then use Build Assembler software to slice the three-dimensional model of pure tungsten metal parts along its height direction to obtain slice data. Then import the slice data into the electron beam selective melting forming equipment; the slice data includes contour data and graphic data of each slice section; the thickness of each layer of the slice processed by the slice is 30 μm;

[0026] Step 2: Put tungsten powder into the powder chamber of the electron beam selective melting forming equipment, and then vacuumize the forming cavity of the electron beam selective melting forming equipment to a vacuum degree of 0.5×10 -2 Pa; the shape of the tungsten powder is spherical, the mass purity is 99.95%, and the powder particle size is less than 30 μm;

[0027] Step 3, using electron bea...

Embodiment 2

[0036] This embodiment includes the following steps:

[0037] Step 1. Use Pro / Engineer software to build a three-dimensional model of pure tungsten metal parts with a size of 10mm×10mm×10mm, and then use Build Assembler software to slice the three-dimensional model of pure tungsten metal parts along its height direction to obtain slice data. Then import the slice data into the electron beam selective melting forming equipment; the slice data includes contour line data and graphic data of each slice section; the thickness of each slice processed by the slice is 100 μm;

[0038] Step 2: Put tungsten powder into the powder chamber of the electron beam selective melting forming equipment, and then vacuumize the forming cavity of the electron beam selective melting forming equipment to a vacuum degree of 1×10 -2Pa; the shape of the tungsten powder is nearly spherical, the mass purity is 99.9%, and the powder particle size is less than 100 μm;

[0039] Step 3, using electron beams ...

Embodiment 3

[0046] This embodiment includes the following steps:

[0047] Step 1. Use Pro / Engineer software to build a three-dimensional model of pure tungsten metal parts with a size of 10mm×10mm×10mm, and then use Build Assembler software to slice the three-dimensional model of pure tungsten metal parts along its height direction to obtain slice data. Then import the slice data into the electron beam selective melting forming equipment; the slice data includes contour line data and graphic data of each slice section; the thickness of each slice processed by the slice is 50 μm;

[0048] Step 2: Put tungsten powder into the powder chamber of the electron beam selective melting forming equipment, and then vacuumize the forming cavity of the electron beam selective melting forming equipment to a vacuum degree of 0.8×10 -2 Pa; the shape of the tungsten powder is spherical, the mass purity is 99.95%, and the powder particle size is less than 50 μm;

[0049] Step 3, using electron beams to pr...

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