POROSITY TEST OF GOLD PLATING CONTACTS AND EVALUATION TEST OF CONNECTORS

摘要

In connection with the deterioration of contacts In connectors, the corrosion caused by the pores is considered as one of the primary factors. In order to make this relation clear, the authors studied the relationship between the pores and thickness of gold plating. Further, the authors studied the contact resistance in the relationships with the pores and with the mechanical wear of the gold plating due to sliding by means of the corrosion test. The detection of the pores was made in the corrosive atmosphere of ammonium polysulfide. This atmosphere blackens nickel and copper in a short time with ease. And further the difference between nickel and copper can be shown by immersing them into sulfuric acid solution. Furthermore, corrosion tests have been carried out in various kinds of atmospheres. The test of this time was made in an atmosphere of gaseous mixture of H_2S + NO_2. Of the evaluation test s of connectors, the compound test, which combines the mechanical wear test and the corrosion test is most recommended.