熱拡散法によるNi-Sn-Zn合金めっき鋼板の特性

抄録

The alloy plating method by the thermal diffusion was developed in order to get the Ni-Sn-Zn alloy plated steel. This new method consists of two processes, at first, Ni, Sn and Zn triple layers are electroplated on the steel in this order and then, the electroplated layers are heated for the diffusion. The structure of this Ni-Sn-Zn alloy consists of the multi-component alloy layers, the surface side consists of Sn-Zn eutectic alloy and the steel base side consists of Zn-Ni and Sn-Ni alloys. The diffused multi-alloy layers on the steel have some interesting properties, such as a good corrosion resistance in the salt spray test and the humidity test, an excellent solderability and the suppression for the occurrence of tin whiskers. Therefore, this thermal-diffused Ni-Sn-Zn alloy coated steel sheets (Ni=0.4, Sn=3.0, Zn=0.5 g/m²) are commercially used for the components of electric appliances.