Unlock instant, AI-driven research and patent intelligence for your innovation.

Brazing flux-free brazing method for aluminum alloy and brazing filler metal paste

A brazing method and flux-free technology, applied in the direction of welding/cutting medium/material, welding medium, welding equipment, etc., can solve the problems of difficult removal of brazing residues, low joint strength, excessive slag inclusions in brazing seams, pores, etc. question

Active Publication Date: 2021-12-03
ZHENGZHOU RES INST OF MECHANICAL ENG CO LTD
View PDF12 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the main components of the cesium fluoroaluminate flux matched with the Zn95Al eutectic solder are CsF and Al3F, with high viscosity, and the brazing residue is difficult to remove, which will further cause the brazing seam Excessive slag inclusions, pores and other defects are formed in the middle, resulting in low joint strength and affecting the service life of castings

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Brazing flux-free brazing method for aluminum alloy and brazing filler metal paste
  • Brazing flux-free brazing method for aluminum alloy and brazing filler metal paste
  • Brazing flux-free brazing method for aluminum alloy and brazing filler metal paste

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0044] The flux-free brazing method of the aluminum alloy of the present embodiment comprises the following steps:

[0045] (1) Coating two cast aluminum alloy surfaces to be welded with a layer of 15-30 μm thick pure zinc layer to obtain galvanized cast aluminum alloy;

[0046] (2) Evenly coat a layer of 3-8μm thick solder paste on the coating of one of the cast aluminum alloys, match it with the coating surface of the other cast aluminum alloy, place it in the rotating magnetic field after fixing, and place the welded part in the sensor;

[0047] The parts by mass of each component of the solder paste are: 75.0 parts of solder powder, 6.0 parts of NdFeB strong magnetic particles, and 3.0 parts of binder. The parts by mass of each component in the solder powder are: 80.0 parts of Zn and 5.0 parts of Al. The particle size of NdFeB strong magnetic particles is 30nm. The binder is polyethylene glycol 200.

[0048](3) Turn on the power, start heating, and heat to 400°C. Under...

Embodiment 2

[0053] The flux-free brazing method of the aluminum alloy of the present embodiment is basically the same as that of Embodiment 1, the only difference being that the parts by mass of the components of the solder paste are: 76.0 parts of solder powder, 7.0 parts of NdFeB strong magnetic particles part, 5.0 parts of binder. The parts by mass of each component in the powder are: 82.0 parts of Zn and 8.0 parts of Al. The particle size of NdFeB strong magnetic particles is 40nm. The binder is terpineol.

Embodiment 3

[0055] The flux-free brazing method of the aluminum alloy of this embodiment is basically the same as that of Embodiment 1, the only difference being that the parts by mass of each component of the solder paste are: 77.0 parts of solder powder, NdFeB strong magnetic particles 8.0 parts, 6.0 parts of binder. The parts by mass of each component in the solder powder are: 85.0 parts of Zn and 10.0 parts of Al. The particle size of NdFeB strong magnetic particles is 50nm. The binder is isopropanol.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
particle diameteraaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

The invention belongs to the field of brazing materials, and particularly relates to a brazing flux-free brazing method for aluminum alloy and brazing filler metal paste. The brazing flux-free brazing method for the aluminum alloy comprises the following steps: (1) plating zinc on a to-be-brazed surface of the aluminum alloy to form a zinc-plated layer; (2) coating the zinc-plated layer with brazing flux-free brazing filler metal paste, wherein the brazing flux-free brazing filler metal paste is composed of a binder and the following components in parts by weight: 70 to 80 parts of zinc-aluminum brazing filler metal and 6.0 to 8.0 parts of rubidium-iron-boron magnetic particles; and (3) heating a to-be-brazed position, making the zinc-plated layer and the zinc-aluminum brazing filler metal form eutectic or near-eutectic brazing filler metal liquid, applying a rotating magnetic field, making the rubidium-iron-boron magnetic particles spin under the action of the rotating magnetic field, and brazing the aluminum alloy without brazing flux. According to the brazing flux-free brazing method, a plating layer and a brazing filler metal layer are diffused under the action of the concentration gradient, and brazing flux-free brazing of the aluminum alloy is achieved under the condition that strong magnetic particles spin to break a film and promote flowing down; and an obtained brazed joint is less in inclusion and air hole defects, relatively compact in brazed seam and high in joint strength.

Description

technical field [0001] The invention belongs to the field of brazing materials, and in particular relates to a flux-free brazing method and brazing paste for aluminum alloys. Background technique [0002] Cast aluminum alloy has low manufacturing cost, light weight, high strength and good low temperature performance, and is widely used in aerospace, ships, automobiles, motorcycles and large equipment. Cast aluminum alloys are prone to defects such as oxidation inclusions, pores, shrinkage porosity, and cracks during the casting process. Due to the inherent defects of cast aluminum alloy castings, welding defects such as inclusions, pores, and cracks are prone to occur during the brazing process. [0003] At present, the commonly used brazing method for cast aluminum alloys is induction or flame brazing in the atmosphere with Zn95Al filler metal and cesium fluoroaluminate flux. Zn95Al is a eutectic solder (a solder with a Zn content of 95% is a eutectic solder, and a solder...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): B23K1/002B23K3/06B23K3/04B23K35/28
CPCB23K1/002B23K3/06B23K3/0475B23K35/282
Inventor 钟素娟龙伟民黄俊兰程亚芳裴夤崟路全彬薛行雁聂孟杰
Owner ZHENGZHOU RES INST OF MECHANICAL ENG CO LTD