Microplasma welding: a decisive step ahead in the battle against welding workpiece deformation

Product design is constantly evolving to meet ongoing demands to reduce weight and manufacturing cost and to increase performance (improved speed, pressure and operating temperature). Materials offering constantly increasing performance are being welded in ever decreasing thicknesses.

The energy input by a welding arc releases localised stresses already in the workpiece (generated by forming, rolling, stamping, etc) and develops other stresses in the environment of the molten area. These phemonena cause geometrical deformations on a scale directly proportional to the energy input. On the other hand, the just sufficient degree of melting in depth and most importantly in width is achieved rapidly with a high energy density process.

The plasma arc welding is unique among welding processes in respect of two criteria: power density, energy input. It is the most powerful electrical arc process. Compared to higher energy processes (electron bombardment in vacuum and laser beam) it is remarkably easy to use. The microplasma arc welding can be used to assemble machined parts without any need for reworking after welding and for the very thin thicknesses (under millimetre)assembly.

The microplasma process has been used successfully on most noble metals (stainless steels, constantan, iron/nickel, cupronickel, copper, nickel/silver, titanium, tantalium, gold …) with the exception of aluminium and its alloys. The process is currently used in various activities sectors :