摘要:
A method of optimizing cycle time and/or casting quality in the making of a cast metal product which has been defined by a CAD product model. The method involves the steps of (a) providing a computer casting model using objective functions that simulate the filling and solidification of the CAD product model within dies, the casting model being subdivided into contiguous regions with each region having terms in at least one of the objective functions for thermal conductivity, heat capacity and cooling time period, (b) populating the objective function terms with experimental data to calibrate the casting model, derive matching heat 1s transfer coefficients for each region, and simulate filling and solidification of the product within the dies, and (c) constraining the objective functions to ensure directional solidification along the series of contiguous sections while optimizing thermal conductivity and heat capacity and iteratively evaluating the constrained objective functions to indicate at least certain regions of the casting model whereby chills and cooling channels may be added, or insulation added to effect improved cycle time and/or casting quality.
摘要:
A steel product with a high austenite grain coarsening temperature having less than 0.4% carbon, less than 0.06% aluminium, less than 0.01% titanium, less than 0.01% niobium, and less than 0.02% vanadium by weight, and having fine oxide particles containing silicon and iron distributed through the steel microstructure having an average particle size less than 50 nanometers and may be between 5 and 30 nanometers. The steel product may have fine oxide particles distributed through the microstructure capable of restricting ferrite recrystallisation for strain levels up to at least 10.0%, for temperatures up to 750 ° C. with holding times up to 20 minutes. The steel product may be made by continuous casting of steel strip introduced between the casting rolls to form a casting pool of molten carbon steel having a total oxygen content of at least 70 ppm usually less than 250 ppm, and a free oxygen content 20 and 60 ppm, counter rotating the casting rolls.