摘要 |
A new surface finishing process for stainless steel where beautiful, bright and milky white coloured surface is obtainable even for such grades as high carbon containing 13 chromium steel and high sulfur containing free cutting stainless steel is disclosed. After removing the surface scale, (1) immerse the stainless steel into the 1st treating solution containing nitric acid: 5-40 g/l, hydrofluoric acid: 2-10 g/l and Fe(III) ion: 15-40 g/l for 5-180 sec., then rinse in water, (2) and successesively immerse into the 2nd treating solution containing nitric acid: 120-250 g/l, Fe(III) ion: 15-40 g/l for 30-300 sec., then rinse in water.
|