The best selection point contact in the form of aluminum alloy welding tooling to reduce the contact area between the tooling and the workpiece. If the tooling surface of the workpiece is contacted, it will soon take the heat of the workpiece, accelerates coagulation bath is not conducive to weld porosity excluded. Tooling pressure hydraulic system is best controlled at 9 ~ 9. 5 MPa.
Too small to reach the preset pressure reverse deformation purposes, but the pressure is too large, but also make binding of the aluminum structure increases. Due to the large linear expansion coefficient of aluminum alloy, high temperature plastic poor, easy to produce large thermal stresses during welding, aluminum structures may cause cracks.
Aluminum welding protection measures
1, before welding by mechanical or chemical means clear the workpiece and the oxide portion and a groove around the wire surface;
2, the welding process to be used to protect a qualified protective gas;
3. When welding, the use of flux, continuously during welding wire prick with bath surface oxide film.