| 摘要 |
1289639 Casting composite ingots; making composite strip ARMCO STEEL CORP 2 Feb 1970 [4 Feb 1969] 4842/70 Headings B3A and B3F A composite metal ingot consists of a unitary stainless steel core having a thickness of at least 0À5% of the thickness of the ingot and a chromium content of at least 11%, sandwiched between and fused to two outer layers of an alloy steel or a carbon steel. Before casting the outer layers around the core the latter has a protective metallic layer applied to it to reduce the loss of chromium from the core during the casting process. This layer preferably consists of mild steel or ingot-iron plates. The ingot may undergo a series of rolling operations to form a strip, in which the stainless steel core has a thickness of at least 0À127 mm. In an example, an ingot having a total thickness of 58 cm. and a stainless steel core 1À27 cm thick was heated to 2350‹ F., rolled to a slab thickness of 17À8 cm., underwent surface conditioning, e.g. by scarfing, was heated to 2380‹ F., rolled to a strip thickness of 0À457 cm, pickled to remove scale and cold-rolled to the desired gauge. The ratio of the strip thickness to the stainless steel core thickness may be between 3 : 1 and 50 : 1. |
