| 摘要 |
A steel composition comprising in wt% C: 0.35 to 1.2, Mn: 0.3 to 3.0, Si: 0.3 to 2.0, Cr: 5.0 to 11.5, Mo: 0.3 to 5.0, Nb: 0.4 to 5.0, V: 0.3 to 3.0, balance iron and incidental impurities. Composite roll formed by welding the steel composition onto a metal core to form a hardface. Optionally heat treating the composite roll (a) stress relieving stage (i) heating the composite roll at a rate of 40 DEG C to 100 DEG C/hour from the welding temperature to within a range of temperatures at which the microstructure of the hardface can stress relieve; (ii) holding the composite roll within the range of temperatures for a sufficient time to allow the microstructure to partially stress relieve; and (iii) air cooling the composite roll to room temperature to partially transform the austenite phase to the martensite phase; (b) first tempering stage (i) heating the composite roll at a rate of 40 DEG C to 100 DEG C/hour to within a range of temperatures to allow the microstructure to temper; (ii) holding the composite roll within the range of temperatures for a sufficient time to allow partial tempering; and (iii) air cooling the composite roll to room temperature; (c) second tempering stage, repeating the first tempering stage. |
