| 摘要 |
PURPOSE:To stop the progress of cracks at a ductile Ti layer and at the same time provide protecting ability by corrosion resistance of Ti by forming, on the inner face of a stainless steel case, more than two layer of coating films comprised of materials such as Ti, TiC or TiN and having corrosion resistance and conductivity. CONSTITUTION:On the inner face of a stainless steel case, more than two layers of film are formed being comprised of materials such as Ti, TiC or TiN and having corrosion resistance and conductivity. By laminating, for example, two layers of Ti, TiC, TiN etc. which have superior corrosion resistance to S than a stainless steel, difference of thermal expansion against a stainless steel can be decreased and reliability is enhanced. By forming multi-layered films more than two piles in this way, progress of cracks can be stopped at TiC/TiN boundary surface whereby cracks penetrating between matrix and a coating film become hard to occur and possibility of reaction of S against a stainless steel can remarkably be reduced, in addition to increment of reliability. |
