Studies on Brazability of Electric Contact Chip Materials (Report I) : Effect of Surface Preparation of Sintered Tungsten Alloys on Wetting of BAg Filler Metals
Effect of surface preparation of sintered tungsten alloys on wetting of BAg alloys was studied. The etching treatment with molten NaNO_2 improved greatly the spreadability of filler alloys by making the surface rich in silver or copper due to the selective corrosion of tungsten in sintered alloys. Moreover, the better spreadability was gained by adding nickel or cobalt to filler alloys or sintered alloys. Then, the spread of filler alloys on sintered tungsten alloys was increased greatly due to nickel or cobalt coated on the surface of sintered alloys, when a flux containing NiCl_2 or CoCl_2 was used.
- Transactions of JWRI
Transactions of JWRI 6 (2), 259-265, 1977-12