Aluminum steel dissimilar metal precoating connecting method

Abstract

A connecting method of an aluminum steel dissimilar metal pre-coating layer relates to the connecting method of the aluminum steel dissimilar metal. The connecting method solves the problems that the prior MIG melt-brazing method is limited by the wettability between an aluminum-based brazing filler metal and a steel plate, so the spreading performance of the brazing filler metal is poor on the steel plate, and the weld formation is poor. Acetone is used for wiping the surface of the steel plate and an aluminum plate, a brush is used for coating a paste which is stirred by the mixed powder and a binder on the surface of the steel plate, a lap joint is composed of the aluminum plate at the upper part and the steel plate at the lower part after the drying of the surface of the steel plate, a MIG welding machine is utilized for passing the melted aluminum plate, the steel plate is simultaneously maintained in a solid state, the self-fluxing brazing connection is formed at one side of the steel plate, and the melt welding connection is formed at the side of the aluminum plate to carrying out the welding of the lap joint. The connecting method improves the spreading performance of the aluminum-based brazing filler metal thereon and finally obtains the aluminum steel dissimilar metal joint with the beautiful shape, excellent mechanical performance and reliable strength, and the tensile strength of the joint can achieve more than 80 percent of an aluminum base material.

Description

technical field [0001] The invention relates to a connection method of dissimilar metals of aluminum and steel. Background technique [0002] The welding between aluminum and steel has always been a hot and difficult problem in the field of connection. The main problem of aluminum and steel welding is that the solid solubility between aluminum and steel is low, the thermal physical properties are quite different, and the two are very easy to react to form brittle Intermetallic compounds, such brittle intermetallic compounds, greatly reduce the mechanical properties of welded joints. The MIG melting-brazing method only melts the aluminum plate to form a fusion welding joint on the aluminum side. At the same time, the molten filler metal and aluminum base material are spread on the steel plate to form a brazed weld. This method is limited by the aluminum-based solder and the steel plate. The wettability between the filler metals leads to poor spreading performance of the sold...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a kind of aluminum-steel dissimilar metal pre-coating connection method, to solve existing MIG fusion-brazing method is limited by the wettability between aluminum-based brazing filler metal and steel plate to cause brazing filler metal on the steel plate Poor spreading performance and poor weld formation