After cleaning, if the storage time is too long (such as more than 24h), it should be reprocessed.

1. Backing plate: the strength of aluminum alloy is very low at high temperature, and the flow performance of liquid aluminum is good. The weld metal is prone to collapse during welding. In order to ensure penetration without collapse, welding is often used to support the molten pool and the nearby metal. The backing plate can be made of graphite plate, stainless steel plate, carbon steel plate, copper plate or copper bar, etc. Open a circular groove on the surface of the backing plate to ensure that the reverse side of the weld is formed. It can also be single-sided welding and double-sided forming without backing plate, but it requires skilled welding operation or adopting advanced technological measures such as strict automatic feedback control of arc welding energy. 3, preheating before welding: thin, small aluminum parts are generally not preheating, thickness of 10mm ~ 15mm can be preheating before welding, according to different types of aluminum alloy preheating temperature can be 100℃ ~ 200℃, available oxygen acetylene flame, electric furnace or torch heating. Preheating can reduce the deformation and porosity of the welding parts. Aluminum alloy after welding wholesale manufacturers

Argon gas is used in welding

2. Cleaning after welding The residual flux and welding slag left in the welding seam and near the welding seam will destroy the passivation film on the aluminum surface and sometimes corrode the aluminum parts, so it should be cleaned up. Simple shape, general requirements of the workpiece can be used hot water scour or steam brush and other simple methods to clean. Aluminum parts with high requirements and complex shape can be washed in hot water with a hard brush, then soaked in chromic anhydride aqueous solution or potassium dichromate solution of 2% ~ 3% at about 60℃ ~ 80℃ for 5min ~ 10min, washed with a hard brush, and then washed in hot water, dried with an oven, or dried with hot air. It can also be naturally dried.