Phase material weldability is poor, therefore , domestic rice Chuan Liu products connections using riveting process

Phase material weldability is poor, therefore , domestic rice Chuan Liu products connections using riveting process . To this end , the development of a single- cycle pulse of platinum foil projection welding of new technology, the two layers as well as the non- cushion foil product key is welded directly . After the lamp is designed with raised bumps , bumps at the current can be concentrated on the internal heat  tungsten filament  the distance between the electrode surfaces , easy to form a temperature gradient in the thickness direction . Meanwhile, the projection welding electrode end face larger than the spot welding , a significant increase of the contact area of ??the electrode and the workpiece , reducing the welding  tungsten carbide rod  and the surface of the heating strength , effectively reduce the sticking of the electrode . Further , since the projection welding heat input can be reduced ( reduced welding current ) , reducing grain products grown , heat welding of the aluminum to improve brittleness . Designed bumps and tested in practice , the choice is less detailed projections play an important part of the benefits . The choice of the shape of the bumps on the suppression of the bump foil tears , generally spherical shape. Spherical bumps having a high strength welded joints , and conical -shaped bumps can remove the residual stress concentration at the bottom and the maximum circumference of the cracks , at the same time , the crush bumps process also easy to produce and move along splash.