standard casting
2.Regression equation of YP and TS has been obtained by using multivariate regression and optimum Ceq range has been found, when Ceq is 0. 48 to 0. 56% (0. 50 to 0. 60% in the case of continuous casting slab), strength properties of hot-rolled 16 to 150 mm plate can be insured to conform to standard.
3.The tests results showed that the ambient tensile properties and the tensile and stress rupture properties at 538 ℃ of the steel ZG15Cr1MoA (C≤0.22%, Cr 0.95%～1.65%, Mo 0.43%～0.67%) cylinder casting for st eam turbine heat treated with normalized at 950 ℃ and tempered at 680 ℃ met the needs of standard requirement.
4.The results show that by controlling the ferrite ductile iron with final silicon content 2.95~2.99%,the graphite size is 0.019~0.017mm in diameter. The graphite nodularization degree increasing up to 2~3 grades with ferrite content of 88.4~94.7% can be directly produced by the instantaneous inoculants and casting. The mechanical properties of ferrite nodular cast iron agree with the requirement of the national-specified standard.
