| 摘要 |
A band of stainless steel, which contains 0.005-0.060% carbon, 10-23% chromium, 0.1-3% aluminium, 0.003-0.030% nitrogen, 0.1-2% manganese and 0.1-2% silicon, with rare earths totalling 0.03-0.15%, is hot and cold-rolled down to 1.5 mms. thick or less, then annealed at 600-1200 degrees C and assembled between two bands of Al of total thickness 0.03-0.32 times that of the steel. The assembly is rolled to a thickness of 0.05-0.25 mms., annealed in hydrogen with a dew point below -30 degrees C to diffuse the Al into the steel and rolled again to reduce its thickness by over 20% with a roughness below 0.25 microns. Also claimed are steel strips so made, characterised by containing 4.5-10% Al for use as catalyst supports and by a resistivity above 1.4 micro-ohm.m for use in electrical resistances. |
