阅读说明：本技术 一种激光选区熔化成形铁基非晶增强铜基偏晶复合材料的方法 (Method for melting and forming iron-based amorphous reinforced copper-based monotectic composite material in selective laser area ) 是由 周圣丰 王小健 杨俊杰 易艳良 张治国 李卫 于 2020-12-09 设计创作，主要内容包括：一种激光选区熔化成形铁基非晶增强铜基偏晶复合材料的方法,该方法的特点为：(1)将要制备的铁基非晶增强铜基偏晶复合材料零件CAD模型分层切片,生成一系列激光选区熔化成形二维扫描轨迹；(2)根据生成的扫描轨迹,逐点、逐线、逐层堆积成三维实体的铜基偏晶复合材料。其中,铜基复合粉末主要由铁基非晶粉末与铜合金粉末按1:9～1:7的质量比组成。采用该方法制备的铜基偏晶复合材料的电导率为50～70％IACS,耐蚀性能是黄铜的1～3倍,耐磨性能是黄铜的8～15倍。(A method for melting and forming an iron-based amorphous reinforced copper-based monotectic composite material in a selective laser area is characterized by comprising the following steps: (1) layering and slicing a CAD model of the iron-based amorphous reinforced copper-based monotectic composite material part to be prepared to generate a series of two-dimensional scanning tracks formed by selective laser melting; (2) and according to the generated scanning track, accumulating point by point, line by line and layer by layer to form the copper-based monotectic crystal composite material of the three-dimensional entity. The copper-based composite powder mainly comprises iron-based amorphous powder and copper alloy powder according to the mass ratio of 1: 9-1: 7. The conductivity of the copper-based monotectic composite material prepared by the method is 50-70% IACS, the corrosion resistance is 1-3 times that of brass, and the wear resistance is 8-15 times that of brass.)

1. A method for melting and forming an iron-based amorphous reinforced copper-based monotectic composite material in a selective laser area is characterized by comprising the following steps of:

(1) uniformly mixing copper-based composite powder in a ball mill, and then placing the mixture in a powder container of a selective laser melting forming machine, wherein the powder mixing technological parameters of the ball mill are as follows: the rotating speed of the ball mill is 60 revolutions per minute, the ball milling atmosphere is helium, the ball milling medium is ethanol, the mass ratio of the zirconia grinding balls to the copper-based monotectic composite powder is 20:1, the diameter of the zirconia grinding balls is 8mm, the ball milling is carried out for 60 hours by adopting a method of ball milling for 20 minutes and then pausing for 15 minutes, and the particle size of the copper-based composite powder after ball milling is 40-60 mu m;

(2) the copper-based composite powder is used as forming powder for selective laser melting, and comprises the following chemical components: the copper-based composite powder mainly comprises iron-based amorphous powder and copper alloy powder in a mass ratio of 1: 9-1: 7, wherein the iron-based amorphous powder comprises the following chemical components: 8-10 wt.% of W, 4-6 wt.% of Cr, 1-3 wt.% of Mo, 1-3 wt.% of Ni, 3-5 wt.% of Si, 3-5 wt.% of B, 0.2-1 wt.% of C, 0.2-1.5 wt.% of Mn, HfO₂0.8-1.5 wt.%, the balance being Fe; the chemical components of the copper alloy powder are as follows: 0.5-2 wt.% of Cr, 1-3 wt.% of Zr, 3-5 wt.% of P, and CeO₂0.2-1 wt.%, and the balance of Cu;

(3) layering and slicing a CAD model of the iron-based amorphous reinforced copper-based monotectic composite material part with the supporting structure, and generating a series of laser selective melting and forming two-dimensional scanning tracks according to slice profile information; vacuumizing a selective laser melting forming chamber, and then filling argon; heating the carbon steel plate with the surface subjected to rust removal and sand blasting treatment to 500-650 ℃; and according to the generated scanning track, accumulating the iron-based amorphous reinforced copper-based monotectic composite material of the three-dimensional entity layer by layer point by point, line by line and layer by adopting a selective laser melting method.

2. The method for selective laser melting forming of the iron-based amorphous reinforced copper-based monotectic composite material according to claim 1, wherein the process parameters for preparing the support structure in the step (3) are as follows: the wavelength of the fiber laser is 1060nm, the laser power is 200W, the height of the supporting structure is 3mm, the laser scanning speed is 480mm/s, the thickness of the layered slice is 60 mu m, and the lap joint rate is 60 percent; the technological parameters for preparing the iron-based amorphous reinforced copper-based monotectic composite material part are as follows: the laser power is 200W, the laser scanning speed is 500-2000 mm/s, the thickness of the layered slice is 60-100 mu m, the lap joint rate is 50-70%, and the copper-based monotectic composite material part is formed by adopting a path mode that the laser scanning directions of two continuous layers are mutually perpendicular until the copper-based monotectic composite material part is manufactured.

3. The method for selective laser melting forming of the iron-based amorphous reinforced copper-based monotectic composite material according to claim 1, wherein the microstructure of the obtained iron-based amorphous reinforced copper-based monotectic composite material is characterized in that: due to liquid phase separation, at solidification speeds up to 10⁸Under the condition of K/s, a large number of 10-20 micron spherical alpha-Fe particles are uniformly embedded in the epsilon-Cu matrix, wherein a large number of M rich in W and Cr are precipitated in the alpha-Fe particles₁₂C and M₂₃C₆Carbide; the electric conductivity of the obtained iron-based amorphous reinforced copper-based monotectic composite material is 50-70% IACS, the corrosion resistance is 1-3 times that of brass, and the wear resistance is 8-15 times that of brass.

Technical Field

The invention relates to a method for melting and forming an iron-based amorphous reinforced copper-based monotectic composite material in a selective laser area, and belongs to the technical field of laser additive manufacturing (3D printing).

Background

In recent years, homogeneous monotectic alloys having liquid phase separation characteristics and unique physical and mechanical properties, which can be used as self-lubricating materials, superconducting materials, electric contact materials, high coercive force permanent magnets and the like, are receiving wide attention from more and more researchers. In general, liquid phase separation is a common phenomenon in condensed systems (such as polymers and alloys), such as Cu-Co, Cu-Fe, Ai-Bi, Fe-Ag, Cu-Sn and the like, when supercooling is below the liquid phase separation temperature, a metastable immiscible region is entered, liquid phase separation occurs, and the microstructure evolves in three stages: firstly, the phase separation process is carried out spontaneously, the alloy melt is subjected to liquid phase separation to form two melts L1 and L2(L1 is a secondary phase alloy melt, and L2 is a main phase alloy melt), a liquid phase with the content of less than 50 percent can be spontaneously contracted into a large number of small droplets due to surface tension, and a liquid phase with the content of more than 50 percent is taken as a matrix liquid phase; then, the main phase alloy melt enters a crystallization process; finally, the small liquid drops enter a solidification stage and are automatically assembled into dispersed spherical particles to be dispersed in the matrix under the action of Marangoni and Stokes.

In particular, the copper-iron based monotectic alloy has the characteristics of high thermal conductivity of copper, low price and soft magnetism of iron, and excellent mechanical and physical properties, which has attracted extensive attention of researchers. However, when the copper-iron monotectic alloy is prepared by the traditional manufacturing method such as fusion casting, the iron-rich liquid drops are easy to generate layering or macro segregation under the action of Marangoni and Stokes, and the application field of the copper-iron monotectic alloy is greatly limited. The results of early extensive studies showed that: at high temperatures, macrosegregation occurs under the stokes force due to the density difference between copper and iron. However, even in space or microgravity conditions, macrosegregation is difficult to avoid, so that under the conditions of ground gravity or pipe drop and the like, the conventional gas spray method, the melt spinning method, the powder metallurgy, the magnetic suspension method and the like are difficult to prepare large-size block homogeneous copper-iron monotectic alloy for engineering.

In recent years, cooling rates of up to 10 have been achieved³～10⁸K/s, and the laser selective melting technology capable of realizing the integrated design and manufacture of the structure and the function is developed rapidly. Under the conditions of rapid heating and rapid solidification, the Stokes motion of the iron-rich liquid drops can be ignored, and an effective way is provided for manufacturing large-size block homogeneous copper-iron monotectic alloy. The amorphous alloy has high strength, high hardness, excellent wear resistance and corrosion resistance, and is used as a reinforcing phase to prepare the metal matrix composite material, so that the performance of the alloy is improved. Particularly, iron-based amorphous alloys, as one of the amorphous alloys, have been widely noticed by researchers due to their excellent physical, chemical and mechanical properties and low cost, such as Zhang et al (Zhang Y J, Zhang J L, Yan Q, et al. Amorphous alloy steel manufacturing by selective laser melting: Enhanced structural and improved corrosion resistance. script material, 2018,148:20-23) Enhanced the strength and wear resistance of stainless steel by introducing iron-based amorphous alloys, and the results show that: the tensile strength of the iron-based amorphous alloy reinforced stainless steel is increased from 819MPa to 1090MPa, and the composite alloy has a lower friction coefficient (from 0.62 to 0.49) and stronger corrosion resistance. Wang et al (Wang Z, Scudino S, Stoica M, et al. Al-based matrix composites re-expressed with short Fe-based metallic glass fiber. journal of Alloys and composites, 2015,651: 170-. However, no research report about the preparation of the iron-based amorphous reinforced copper-based monotectic composite material by adopting the selective laser melting forming technology at home and abroad is discovered so far.

Disclosure of Invention

The invention aims to provide a method for melting and forming a bulk iron-based amorphous reinforced copper-based monotectic composite material by selective laser. The invention is realized by the following steps:

(1) uniformly mixing copper-based composite powder in a ball mill, and then placing the mixture in a powder container of a selective laser melting forming machine, wherein the powder mixing technological parameters of the ball mill are as follows: the rotating speed of the ball mill is 60 revolutions per minute, the ball milling atmosphere is helium, the ball milling medium is ethanol, and the mass ratio of the zirconia grinding balls to the copper-based monotectic composite powder is 20:1, ball milling for 60 hours by adopting a method of ball milling for 20 minutes and then suspending for 15 minutes, wherein the diameter of a zirconium oxide grinding ball is 8mm, and the particle size of copper-based monotectic composite powder after ball milling is 40-60 mu m;

(2) the copper-based composite powder is used as forming powder for selective laser melting, and comprises the following chemical components: the copper-based composite powder mainly comprises iron-based amorphous powder and copper alloy powder in a mass ratio of 1: 9-1: 7, wherein the iron-based amorphous powder comprises the following chemical components: 8-10 wt.% of W, 4-6 wt.% of Cr, 1-3 wt.% of Mo, 1-3 wt.% of Ni, 3-5 wt.% of Si, 3-5 wt.% of B, 0.2-1 wt.% of C, 0.2-1.5 wt.% of Mn, HfO₂0.8-1.5 wt.%, the balance being Fe; the chemical components of the copper alloy powder are as follows: 0.5-2 wt.% of Cr, 1-3 wt.% of Zr, 3-5 wt.% of P, and CeO₂0.2-1 wt.%, and the balance of Cu.

(3) Layering and slicing a CAD model of the iron-based amorphous reinforced copper-based monotectic composite material part with the supporting structure, and generating a series of laser selective melting and forming two-dimensional scanning tracks according to slice profile information; vacuumizing a selective laser melting forming chamber, and then filling argon; heating the carbon steel plate with the surface subjected to rust removal and sand blasting treatment to 500-650 ℃; and according to the generated scanning track, accumulating the copper-based monotectic composite material of the three-dimensional entity layer by layer point by point, line by line and layer by adopting a selective laser melting method.

In the step (3), the process parameters for preparing the support structure are as follows: the wavelength of the fiber laser is 1060nm, the laser power is 200W, the height of the supporting structure is 3mm, the laser scanning speed is 480mm/s, the thickness of the layered slice is 60 mu m, and the lap joint rate is 60 percent; the technological parameters for preparing the iron-based amorphous reinforced copper-based monotectic composite material part are as follows: the laser power is 200W, the laser scanning speed is 500-2000 mm/s, the thickness of the layered slice is 60-100 mu m, the lap joint rate is 50-70%, and the copper-based monotectic composite material part is formed by adopting a path mode that the laser scanning directions of two continuous layers are mutually perpendicular until the copper-based monotectic composite material part is manufactured.

In the step (3), the microstructure of the obtained iron-based amorphous reinforced copper-based monotectic composite material is characterized in that: a large number of 10-20 micron spherical alpha-Fe particles are uniformly embedded in the epsilon-Cu matrix, wherein a large number of M rich in W and Cr are precipitated in the alpha-Fe particles₁₂C and M₂₃C₆Carbide; the electric conductivity of the obtained iron-based amorphous reinforced copper-based monotectic composite material is 50-70% IACS, the corrosion resistance is 1-3 times that of brass, and the wear resistance is about 8-15 times that of brass.

Compared with the prior art, the invention has the following advantages and beneficial effects:

(1) the bulk iron-based amorphous reinforced copper-based monotectic composite material with a complex shape can be prepared; (2) due to liquid phase separation, at solidification speeds up to 10⁸Under the condition of K/s, the bulk iron-based amorphous reinforced copper-based monotectic composite material mainly comprises the following components in percentage by weight: epsilon-Cu matrix and spherical alpha-Fe particles, wherein M rich in W and Cr is greatly precipitated in the alpha-Fe particles₁₂C and M₂₃C₆Carbide; (3) the conductivity of the block iron-based amorphous reinforced copper-based monotectic composite material is 50-70% IACS, the corrosion resistance is 1-3 times that of brass, and the wear resistance is about 8-15 times that of brass.

Detailed Description

The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.

Example 1

The carbon steel plate after rust removal and sand blasting is used as a base material, a laser selective melting forming method is adopted to prepare the block iron-based amorphous reinforced copper-based monotectic composite material, and the solidification speed is up to 10 due to liquid phase separation⁸Under the condition of K/s, the microstructure characteristics of the obtained block iron-based amorphous reinforced copper-based monotectic composite material are as follows: a large number of 10-20 micron spherical alpha-Fe particles are uniformly embedded in the epsilon-Cu matrix, wherein a large number of M rich in W and Cr are precipitated in the alpha-Fe particles₁₂C and M₂₃C₆The electric conductivity of the iron-based amorphous reinforced copper-based monotectic composite material obtained by the carbide is 50 percent IACS, the corrosion resistance is 3 times that of brass, and the wear resistance is about the same15 times as much brass. The specific implementation process is as follows:

(1) uniformly mixing copper-based composite powder in a ball mill, and then placing the mixture in a powder container of a selective laser melting forming machine, wherein the powder mixing technological parameters of the ball mill are as follows: the rotating speed of the ball mill is 60 revolutions per minute, the ball milling atmosphere is helium, the ball milling medium is ethanol, the mass ratio of the zirconia grinding balls to the copper-based monotectic composite powder is 20:1, the diameter of the zirconia grinding balls is 8mm, the ball milling is carried out for 60 hours by adopting a method of ball milling for 20 minutes and then pausing for 15 minutes, and the particle size of the copper-based monotectic composite powder after ball milling is 40-60 mu m;

(2) copper-based composite powder is used as forming powder for selective laser melting, the copper-based composite powder mainly comprises iron-based amorphous powder and copper alloy powder according to the mass ratio of 1:7, and the iron-based amorphous powder comprises the following chemical components: w10 wt.%, Cr 6 wt.%, Mo 3 wt.%, Ni 3 wt.%, Si 5 wt.%, B5 wt.%, C0.3 wt.%, Mn 1.5 wt.%, HfO₂1.5 wt.%, balance Fe; the chemical components of the copper alloy powder are as follows: 0.5 wt.% Cr, 1.0 wt.% Zr, 3.0 wt.% P, CeO₂1.0 wt.%, balance Cu;

(3) layering and slicing a CAD model of the iron-based amorphous reinforced copper-based monotectic composite material part with the supporting structure, and generating a series of laser selective melting and forming two-dimensional scanning tracks according to slice profile information; vacuumizing a selective laser melting forming chamber, and then filling argon; heating the carbon steel plate with the surface subjected to rust removal and sand blasting treatment to 650 ℃; and according to the generated scanning track, accumulating the copper-based monotectic composite material of the three-dimensional entity layer by layer point by point, line by line and layer by adopting a selective laser melting method.

The process parameters for preparing the support structure are as follows: the wavelength of the fiber laser is 1060nm, the laser power is 200W, the height of the supporting structure is 3mm, the laser scanning speed is 480mm/s, the thickness of the layered slice is 60 mu m, and the lap joint rate is 60 percent; the technological parameters for preparing the iron-based amorphous reinforced copper-based monotectic composite material part are as follows: the laser power is 200W, the laser scanning speed is 800mm/s, the thickness of the layered slice is 100 μm, the lap joint rate is 70%, and the continuous forming is carried out in a way that the laser scanning directions between two layers are mutually perpendicular until the manufacturing of the copper-based monotectic composite material part is completed.

Example 2

The carbon steel plate after rust removal and sand blasting is used as a base material, a laser selective melting forming method is adopted to prepare the block iron-based amorphous reinforced copper-based monotectic composite material, and the solidification speed is up to 10 due to liquid phase separation⁸Under the condition of K/s, the microstructure characteristics of the obtained block iron-based amorphous reinforced copper-based monotectic composite material are as follows: a large number of 10-20 micron spherical alpha-Fe particles are uniformly embedded in the epsilon-Cu matrix, wherein a large number of M rich in W and Cr are precipitated in the alpha-Fe particles₁₂C and M₂₃C₆The electric conductivity of the iron-based amorphous reinforced copper-based monotectic composite material obtained by the carbide is 60% IACS, the corrosion resistance is 2 times that of brass, and the wear resistance is about 10 times that of the brass. The specific implementation process is as follows:

(1) uniformly mixing copper-based composite powder in a ball mill, and then placing the mixture in a powder container of a selective laser melting forming machine, wherein the powder mixing technological parameters of the ball mill are as follows: the rotating speed of the ball mill is 60 revolutions per minute, the ball milling atmosphere is helium, the ball milling medium is ethanol, the mass ratio of the zirconia grinding balls to the copper-based monotectic composite powder is 20:1, the diameter of the zirconia grinding balls is 8mm, the ball milling is carried out for 60 hours by adopting a method of ball milling for 20 minutes and then pausing for 15 minutes, and the particle size of the copper-based monotectic composite powder after ball milling is 40-60 mu m;

(2) copper-based composite powder is used as forming powder for selective laser melting, the copper-based composite powder mainly comprises iron-based amorphous powder and copper alloy powder according to the mass ratio of 1:8, and the iron-based amorphous powder comprises the following chemical components: w9.0 wt.%, Cr 5.0 wt.%, Mo 2.0 wt.%, Ni 2.0 wt.%, Si 4.0 wt.%, B4.0 wt.%, C0.8 wt.%, Mn 0.8 wt.%, HfO₂1.2 wt.%, balance Fe; the chemical components of the copper alloy powder are as follows: cr 1.5 wt.%, Zr 2.0 wt.%, P4.0 wt.%, CeO₂0.6 wt.%, balance Cu;

(3) layering and slicing a CAD model of the iron-based amorphous reinforced copper-based monotectic composite material part with the supporting structure, and generating a series of laser selective melting and forming two-dimensional scanning tracks according to slice profile information; vacuumizing a selective laser melting forming chamber, and then filling argon; heating the carbon steel plate with the surface subjected to rust removal and sand blasting treatment to 600 ℃; and according to the generated scanning track, accumulating the copper-based monotectic composite material of the three-dimensional entity layer by layer point by point, line by line and layer by adopting a selective laser melting method.

The process parameters for preparing the support structure are as follows: the wavelength of the fiber laser is 1060nm, the laser power is 200W, the height of the supporting structure is 3mm, the laser scanning speed is 480mm/s, the thickness of the layered slice is 60 mu m, and the lap joint rate is 60 percent; the technological parameters for preparing the iron-based amorphous reinforced copper-based monotectic composite material part are as follows: the laser power is 200W, the laser scanning speed is 1500mm/s, the thickness of the layered slice is 80 μm, the lap joint rate is 60%, and the continuous forming is carried out in a way that the laser scanning directions between two layers are mutually perpendicular until the manufacturing of the copper-based monotectic composite material part is completed.

Example 3

The carbon steel plate after rust removal and sand blasting is used as a base material, a laser selective melting forming method is adopted to prepare the block iron-based amorphous reinforced copper-based monotectic composite material, and the solidification speed is up to 10 due to liquid phase separation⁸Under the condition of K/s, the microstructure characteristics of the obtained block iron-based amorphous reinforced copper-based monotectic composite material are as follows: a large number of 10-20 micron spherical alpha-Fe particles are uniformly embedded in the epsilon-Cu matrix, wherein a large number of M rich in W and Cr are precipitated in the alpha-Fe particles₁₂C and M₂₃C₆The electric conductivity of the iron-based amorphous reinforced copper-based monotectic composite material obtained by the carbide is 70% IACS, the corrosion resistance is 1 time that of brass, and the wear resistance is about 8 times that of the brass. The specific implementation process is as follows:

(1) uniformly mixing copper-based composite powder in a ball mill, and then placing the mixture in a powder container of a selective laser melting forming machine, wherein the powder mixing technological parameters of the ball mill are as follows: the rotating speed of the ball mill is 60 revolutions per minute, the ball milling atmosphere is helium, the ball milling medium is ethanol, and the mass ratio of the zirconia grinding balls to the copper-based monotectic composite powder is 20:1, ball milling for 60 hours by adopting a method of ball milling for 20 minutes and then suspending for 15 minutes, wherein the diameter of a zirconium oxide grinding ball is 8mm, and the particle size of copper-based monotectic composite powder after ball milling is 40-60 mu m;

(2) the copper-based composite powder is used as forming powder for selective laser melting, and mainly comprisesThe iron-based amorphous powder and the copper alloy powder are composed in a mass ratio of 1:9, and the iron-based amorphous powder comprises the following chemical components: w8.0 wt.%, Cr 4.0 wt.%, Mo 1.0 wt.%, Ni 1.0 wt.%, Si 3.0 wt.%, B3.0 wt.%, C0.25 wt.%, Mn 0.3 wt.%, HfO₂0.85 wt.%, balance Fe; the chemical components of the copper alloy powder are as follows: 0.6 wt.% Cr, 1.5 wt.% Zr, 3.2 wt.% P, CeO₂0.3 wt.%, balance Cu;

(3) layering and slicing a CAD model of the iron-based amorphous reinforced copper-based monotectic composite material part with the supporting structure, and generating a series of laser selective melting and forming two-dimensional scanning tracks according to slice profile information; vacuumizing a selective laser melting forming chamber, and then filling argon; heating the carbon steel plate with the surface subjected to rust removal and sand blasting treatment to 500 ℃; and according to the generated scanning track, accumulating the copper-based monotectic composite material of the three-dimensional entity layer by layer point by point, line by line and layer by adopting a selective laser melting method.

The process parameters for preparing the support structure are as follows: the wavelength of the fiber laser is 1060nm, the laser power is 200W, the height of the supporting structure is 3mm, the laser scanning speed is 480mm/s, the thickness of the layered slice is 60 mu m, and the lap joint rate is 60 percent; the technological parameters for preparing the iron-based amorphous reinforced copper-based monotectic composite material part are as follows: the laser power is 200W, the laser scanning speed is 2000mm/s, the thickness of the layered slice is 60 mu m, the lap joint rate is 50 percent, and the copper-based monotectic composite material part is formed by adopting a path mode that the laser scanning directions of two continuous layers are mutually vertical until the manufacture of the copper-based monotectic composite material part is finished.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.