Process for improving the resistance to corrosion of stainless steel
AssigneeSanyo Electric Co., Ltd.
InventorsMakoto Fukushima, Kikuo Takizawa
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Abstract
There is provided a process for improving the resistance to corrosion of stainless steel by ion plating process, the process comprising coating a component-adjusted stainless steel having an Mn/S ratio of less than 100 as substrate with a Ti-layer for surface preparation, coating directly the resulting Ti-layer or indirectly a TiC-layer, which has been coated onto the Ti-layer in advance as intermediate, with a TiN-layer in a total thickness of 1 to 3 .mu.m. The TiN-coated stainless steel according to the present invention may be widely used as corrosion-resistant metallic materials for preparing articles which can be employed under wet conditions such as tableware.
Claims2
A process for improving the resistance to corrosion of a stainless steel, the process comprising coating the stainless steel having an Mn/S ratio of less than 100 as substrate by ion plating process with a Ti-layer for surface preparation, coating directly the resulting Ti-layer or indirectly a TiC-layer, which has been coated onto the Ti-layer in advance as intermediate, with a TiN-layer in a total thickness of 1 to 3 .mu.m, the composition of the substrate comprising the following A or B:
- ______________________________________ A B % by Wt. Element % by Wt. Element ______________________________________ less than 0.08 C less than 0.08 C less than 1.0 Si less than 1.0 Si less than 1.0 Mn less than 1.0 Mn less than 0.04 P less than 0.04 P less than 0.01 S 0.005 to 0.010 S 8.0 to 12.0 Ni 8.0 to 12.0 Ni 17.0 to 20.0 Cr 17.0 to 20.0 Cr 0.40 to 0.80 Mo 0.40 to 0.80 Mo the balance Fe the balance Fe. ______________________________________
A process for improving the resistance to corrosion of a stainless steel, the process comprising coating the stainless steel by ion plating process with a Ti-layer for surface preparation, coating directly the resulting Ti-layer or indirectly a TiC-layer, which has been coated onto the Ti-layer in advance as intermediate, with a TiN-layer in a total thickness of 1 to 3 .mu.m, the composition of the substrate comprising the following A or B:
- ______________________________________ A B % by Wt. Element % by Wt. Element ______________________________________ less than 0.08 C less than 0.08 C less than 1.0 Si less than 1.0 Si less than 0.7 Mn less than 0.7 Mn less than 0.04 P less than 0.04 P less than 0.005 S less than 0.005 S 8.0 to 12.0 Ni 8.0 to 12.0 Ni 17.0 to 20.0 Cr 17.0 to 20.0 Cr 0.40 to 0.80 Mo 0.40 to 0.80 Mo 0.30 to 0.50 Cu 0.10 to 0.30 Cu the balance Fe 0.03 to 0.12 Bi the balance Fe ______________________________________
Dependencies are inferred from the claim text.