Characteristics after Rolling and Aging of Cu-Ni-Sn Alloys that have Reflowed Tin Plating or several Immersing Treatments

Abstract

Spring limits, contact resistance and solderability after cold rolling and aging treatments on four surface treatments of thin plates made of Cu-Ni-Sn alloys are investigated.The results are as follows;1) Spring limits are strongly affected by aging treatments. The preferred treatment condition is 523-623K, for 30min.2) Surface properties are improved by pretreatments after active flux or pickle.3) Mechanical properties after cold rolling are not influenced by surface treatments.4) Contact resistance and solderability are strongly affected by cold rolling or aging treatments, due to the formation of tin oxide film on the surface.