SILVER-NICKEL ELECTRICAL CONTACT POINT MATERIAL

摘要

PURPOSE:To obtain an electrical contact point material having superior electric arc resistance by allowing the specified amount of Ni to enter into solid soln. in Ag in a supersatd. state by powder metallurgical processing and by mixing the resulting alloy powder with Ni powder so as to blend Ag with Ni in a specified ratio. CONSTITUTION:Ag-Ni alloy powder is produced by allowing 1-5wt% Ni to enter into solid soln. in Ag in a supersatd. state by a method for producing powder by very rapid cooling. The alloy powder is mixed with the prescribed amount of Ni powder to produce an electrical contact point material consisting of 5-40wt% Ni and the balance Ag. The desirable particle size of the Ag-Ni alloy powder is <=about 44mum and that of the Ni powder is <=about 10mum. The electrical contact point material is slightly consumed, undergoes no increase in the contact resistance and causes hardly melt sticking even when it is frequently exposed to electric arc by switching.