CN111618293A

CN111618293A - Method for preparing copper-iron alloy net by powder rolling process

Info

Publication number: CN111618293A
Application number: CN202010514139.3A
Authority: CN
Inventors: 陈存广; 张陈增; 韩未豪; 郭志猛; 秦乾; 李沛; 陆天行
Original assignee: University of Science and Technology Beijing USTB
Current assignee: University of Science and Technology Beijing USTB
Priority date: 2020-06-08
Filing date: 2020-06-08
Publication date: 2020-09-04
Anticipated expiration: 2040-06-08
Also published as: CN111618293B

Abstract

The invention provides a method for preparing a copper-iron alloy net by a powder rolling process, and relates to the field of powder metallurgy. The process comprises the steps of utilizing element mixed powder of copper and iron, forming by powder rolling, combining with the subsequent sintering process, sintering at the temperature of 600-1000 ℃ for 1-6 h, and preparing the porous copper-iron alloy mesh. The invention can freely regulate and control the content of iron and the size of micropores in the copper-iron alloy, iron particles are uniformly and finely distributed in copper, the problem that the porous copper-iron alloy electromagnetic shielding net is difficult to prepare by the traditional casting process is solved by flexibly changing the rolling process parameters to form the electromagnetic shielding net at one time, and the invention has important application prospect in the fields of 5G communication, robot communication control and the like.

Description

Method for preparing copper-iron alloy net by powder rolling process

Technical Field

The invention belongs to the field of powder metallurgy, and relates to a method for preparing a copper-iron alloy net by a powder rolling process.

Background

The copper-iron alloy (the iron content is 5-50 wt%) has excellent thermal conductivity and electromagnetic wave shielding property, and can be used for sensitive equipment of an electronic system to reduce external electromagnetic interference, such as AM/FM radio waves, CRT oscilloscopes and the like. In actual work, any electrical equipment needs to dissipate heat, so that it is important to reserve corresponding gaps on the shielding material to form the metal shielding material with the net structure. The copper-iron alloy mesh is a good shielding product and has very wide application potential.

However, the copper-iron alloy belongs to a metastable immiscible alloy, two phases have very high positive enthalpy value and are basically not dissolved in solid at normal temperature, the copper-iron two phases are separated to form coarse segregated dendrites due to solid-liquid phase change in the traditional smelting and netting combined process for preparing the high-iron-content copper-iron alloy netting, the two phases are layered in structure, the braiding technology is difficult to achieve, the formed meshes are large in size and uneven in distribution, time is consumed, and low efficiency is achieved, and the wide application of the copper-iron alloy in the field of electromagnetic shielding is limited. Patent application numbers cn201910782289.x and CN 201910510053.0 disclose that the traditional smelting is combined with subsequent deformation processing and net weaving processes to prepare the copper-iron alloy for electromagnetic shielding, but the prepared tissue iron particles are coarse and segregated, the mesh size is large and uneven, the process is complex, the production efficiency is low, and the shielding performance is low.

Disclosure of Invention

The invention aims to provide a simple and efficient preparation method of a porous copper-iron alloy shielding net, which has fine and uniform pore diameter distribution and thin thickness, copper and iron are uniformly and finely distributed, and the mesh size can be freely adjusted.

The technical principle of the invention is as follows: preparing mixed powder of copper and iron according to a certain proportion, pouring the powder into a rolling mill for powder rolling, freely controlling the mesh size of a green body by adjusting rolling process parameters, and then sintering the green body to obtain the copper-iron alloy shielding net containing micropores and being thin in thickness.

In order to realize the technical scheme of the invention, the specific preparation process comprises the following steps:

(1) preparing a powder raw material: weighing 5-50% of Fe by mass of the pure Cu powder and the pure Fe powder, and mixing in a mixer for 1-10 h to prepare uniform mixed powder.

(2) Powder rolling: a 45-degree inclined rolling mill is adopted, and the raw blank with the thickness of 0.2-2 mm, the width of 50-500 mm and the length of 100-5000 mm is rolled by using the self weight of the powder and the friction between the roller and the powder.

(3) And (3) sintering: and placing the rolled green body on a support plate, and sintering in a vacuum or hydrogen sintering furnace at the sintering temperature of 600-1000 ℃ for 1-6 h to form the copper-iron alloy electromagnetic shielding net with the aperture of 2-2000 meshes.

Preferably, the pure Cu powder in step (1) may be one or more of electrolytic Cu powder, reduced Cu powder, and atomized Cu powder, and the pure Fe powder may be one or more of electrolytic Fe powder, carbonyl Fe powder, reduced Fe powder, and atomized Fe-Fe powder.

Compared with the traditional process, the invention has the beneficial effects that:

(1) the powder rolling can realize the one-step forming of the copper-iron alloy thin strip with the micropore net structure, and the mesh size and the shape can be controlled.

(2) The copper and iron components are flexible and controllable, the two phases are uniformly distributed, no segregation exists, and the comprehensive performance is excellent.

(3) The method has the advantages of short process flow, high yield, high preparation efficiency, simple operation, low cost, capability of realizing continuous production and important application prospect in the fields of 5G communication, robot communication control and the like.

Detailed Description

Example 1

a. 14.7 g of electrolytic Cu powder having an average particle size of 10 μm and 14.7 g of electrolytic Fe powder having an average particle size of 10 μm were mixed, and the above powders were mixed for 10 hours by a V-type blender.

b. Feeding with Russian two-roll 45-degree inclined rolling mill at normal temperature at 1/m-min rolling speed by using powder dead weight and friction force between the rolls and the powder^-1And rolling to obtain a green compact with the thickness of 0.2 mm, the width of 50 mm and the length of 500 mm.

c. The rolled green body is placed on a supporting plate and is placed into a vacuum sintering furnace for sintering, the sintering temperature is 600 ℃, the heating rate is 5 ℃/min, the sintering time is 1 h, a copper-iron alloy net with 50 wt% of iron content, 2000 meshes of mesh size and 30% of porosity is obtained, the iron phase is fine and is uniformly distributed, the shielding effectiveness is 130 dB when the electromagnetic wave frequency is 450 MHz, and the shielding performance is improved by 35% compared with the traditional smelting and net weaving process.

Example 2

a. 18.1 kg of atomized Cu powder having an average particle size of 150 μm and 7.7 kg of atomized Fe powder having an average particle size of 150 μm were mixed, and the above powders were mixed for 1 hour by a V-type mixer.

b. Feeding with Russian two-roll 45-degree inclined rolling mill at normal temperature at 1/m-min rolling speed by using powder dead weight and friction force between the rolls and the powder^-1And rolling to obtain a green body with the thickness of 2 mm, the width of 500 mm and the length of 5000 mm.

c. The rolled green body is placed on a supporting plate and is placed into a hydrogen sintering furnace for sintering, the sintering temperature is 1000 ℃, the heating rate is 3 ℃/min, the sintering time is 6 hours, a copper-iron alloy net with the iron content of 30 wt.%, the mesh size of 2 meshes and the porosity of 40% is obtained, the iron phase is fine and is uniformly distributed, the shielding effectiveness is 125 dB when the electromagnetic wave frequency is 450 MHz, and the shielding performance is improved by 30% compared with the traditional smelting and net weaving process.

Example 3

a. 318.2 g of reduced Cu powder having an average particle size of 10 μm and 35.4 g of carbonyl Fe powder having an average particle size of 1 μm were mixed, and the above powders were mixed for 6 hours using a V-type mixer.

b. Feeding with Russian two-roll 45-degree inclined rolling mill at normal temperature at 1/m-min rolling speed by using powder dead weight and friction force between the rolls and the powder^-1And rolling to obtain a green body with the thickness of 0.5 mm, the width of 200 mm and the length of 500 mm.

c. The rolled green body is placed on a supporting plate and is placed into a vacuum sintering furnace for sintering, the sintering temperature is 800 ℃, the heating rate is 5 ℃/min, the sintering time is 2 h, a copper-iron alloy net with the iron content of 10 wt.%, the mesh size of 500 meshes and the porosity of 20% is obtained, the iron phase is fine and is uniformly distributed, the shielding effectiveness is 110 dB when the electromagnetic wave frequency is 450 MHz, and the shielding performance is improved by 30% compared with the traditional smelting and net weaving process.

Example 4

a. 6.32 kg of atomized Cu powder having an average particle size of 75 μm and 0.33 kg of reduced Fe powder having an average particle size of 10 μm were mixed, and the above powders were mixed for 3 hours using a V-type blender.

b. Feeding at room temperature with Russian two-roll 45-degree inclined rolling mill by using the dead weight of the powder and the friction between the rolls and the powder, and rolling at a speed of 1/m.min^-1And rolling to obtain a green compact with the thickness of 1.5 mm, the width of 400 mm and the length of 2500 mm.

c. The rolled green body is placed on a supporting plate and is placed into a hydrogen sintering furnace for sintering, the sintering temperature is 900 ℃, the heating rate is 2 ℃/min, the sintering time is 4 h, a copper-iron alloy net with the iron content of 5 wt.%, the mesh size of 100 meshes and the porosity of 50% is obtained, the iron phase is fine and is uniformly distributed, the shielding effectiveness is 95 dB when the electromagnetic wave frequency is 450 MHz, and the shielding performance is improved by 20% compared with the traditional smelting and net weaving process.

Claims

1. A method for preparing a copper-iron alloy net by a powder rolling process is characterized by comprising the following steps: the method comprises the following process steps:

(1) preparing a powder raw material: weighing 5-50% of the weight of Fe in the pure Cu powder and the pure Fe powder, and mixing in a mixer for 1-10 h to prepare uniform mixed powder;

(2) powder rolling: feeding by using the self weight of the powder and the friction force between the roller and the powder by adopting a 45-degree inclined rolling mill, and rolling to obtain a green body with the thickness of 0.2-2 mm, the width of 50-500 mm and the length of 10-5000 mm;

2. The method for preparing the copper-iron alloy mesh by the powder rolling process according to claim 1, wherein the method comprises the following steps: the pure Cu powder in the step (1) can be one or more of electrolytic Cu powder, reduced Cu powder and atomized Cu powder, and the pure Fe powder can be one or more of electrolytic Fe powder, carbonyl Fe powder, reduced Fe powder and atomized Fe powder.