Measures Against Oxide Film
Oxide film affects contact resistance although it causes no problem in conductivity.
The following two measures can be taken for oxide film.
- Perform finish plating after low-temperature heat treatment to remove oxide film.
- Prevent generation of oxide film by conducting non-oxidation heat treatment.
Method 1: Perform finish plating after low-temperature heat treatment to remove oxide film.
When you perform gold or other types of finish plating to “Mac Wire CP” after the spring-forming process and the low-temperature heat treatment, you can remove oxide film in the pre-treatment process of the finish plating.
Furthermore, the copper plating in “Mac Wire CP” effectively works as a base for finish plating, which can enhance the quality of finish plating.
From the perspective of conductive performance, since conductivity (13%–15％) of “Mac Wire CP” is added to the finish plating, you can make springs with excellent conductivity and contact resistance.
Method 2: Prevent generation of oxide film by conducting non-oxidation heat treatment.
You can prevent the generation of oxide film by adopting the heat treatment method using a vacuum furnace or an non-oxidation reducing gas atmosphere furnace.
You can eliminate the oxide film removal process and the conductive gold or nickel-plating process, which contributes to cost reductions.