摘要 |
A refiner disk or disk segment is cast from a stainless steel alloy having a composition of 0.2 percent to 0.4 percent carbon, 0.5 to 1.5 percent manganese, 0.5 percent to 1.5 percent silicon, a maximum of 0.05 percent sulfur, a maximum of 0.05 percent phosphorus, 14 percent to 18 percent chromium, 2 percent to 5 percent nickel, 2 percent to 5 percent copper, a maximum of 1 percent molybdenum, and 1.5 percent to 2.5 percent niobium, the balance being iron. The Niobium forms discrete carbides at high temperatures during the melting process. Upon cooling, the carbides are distributed evenly throughout the structure. This resultant alloy provides toughness and corrosion resistance like a lower carbon alloy plus increased wear resistance due to the carbide formation. The alloy utilizes chromium to impart corrosion resistance, the process of tying up carbon as discrete, non-chromium carbides increases the amount of chromium present to provide corrosion resistance.
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