New powder metallurgical Ag/SnO2 contact material for different loads

In the scope of further development of sintered, extruded AgSnO₂, a new variant is introduced, which differs from the earlier materials by the use of different additives. The new material is clearly more resistive to erosion at make, particularly in switching devices with a high degree of bounce in normal operation, than earlier AgSnO₂ and AgCdO materials. It has been found, under certain conditions, to compensate to a large extent for disadvantageous combination of effects of "synchronism", "phase succession" and "switching delay", which are the cause of large variations in life. The new material also gives a considerably higher resistance to welding on make, and at heavy duty it has advantages in many applications.