The properties of cast iron grade GL 250 are dependent on the microstructures developed during casting. These microstructures are in turn dependent on the composition of the alloy, type of mould and other numerous cas...The properties of cast iron grade GL 250 are dependent on the microstructures developed during casting. These microstructures are in turn dependent on the composition of the alloy, type of mould and other numerous casting practice variables such as shake-out time, pouring temperature, mould ambient conditions and inoculating technique. In this work, the effect of silicon content and shake-out time on the grain size (GS) and hardness properties of GL 250 cast iron was studied using a pouring temperature of 1400℃ and sand mould casting. Using charge materials consisting of pig iron and other additives, GL 250 castings containing silicon contents of 1.7, 2.1 and 2.7% were casted using a constant pouring temperature of 1400℃, molding sand of specified properties and ambient mould temperature of 32℃. Results showed that type A flake type was obtained at 30mins shakeout time for all samples for the C.I composition under study. Increasing shake-out time decreased hardness and increased carbide grain size. Increasing silicon content was observed to increase grain size and reduce free graphite but with resultant decrease in hardness. Two mathematical relationships were derived. One related grain-size to silicon content and shakeout time while the second related Brinnel Hardness to Silicon content and shake-out time. They are: Grain Size=0.40 Si+0.17Shake-out Time-0.15 and BHN=-60.53Si-7.15Shake-out Time+329.35 at 1400℃ pouring temperature in a molding sand of specified properties and sand mould ambient temperature of 32℃.展开更多
Casting simulation tool ADSTEFAN is useful to design casting technology of complicated iron castings.Based on the function of solidification analysis,special methods were taken to carry out the prediction and optimiza...Casting simulation tool ADSTEFAN is useful to design casting technology of complicated iron castings.Based on the function of solidification analysis,special methods were taken to carry out the prediction and optimization of shake-out timing for large sized iron castings.It has been proved that these analyses are effective to iron casting production.During the research of cast iron semi-solid process,to predict and control the influence of inclined cooling plate on flow and heat transmission of molten iron,the basis of analysis model has been built in this study.Flow field simulation considering temperature field was carried out for further research and satisfied with the practical production.展开更多
文摘The properties of cast iron grade GL 250 are dependent on the microstructures developed during casting. These microstructures are in turn dependent on the composition of the alloy, type of mould and other numerous casting practice variables such as shake-out time, pouring temperature, mould ambient conditions and inoculating technique. In this work, the effect of silicon content and shake-out time on the grain size (GS) and hardness properties of GL 250 cast iron was studied using a pouring temperature of 1400℃ and sand mould casting. Using charge materials consisting of pig iron and other additives, GL 250 castings containing silicon contents of 1.7, 2.1 and 2.7% were casted using a constant pouring temperature of 1400℃, molding sand of specified properties and ambient mould temperature of 32℃. Results showed that type A flake type was obtained at 30mins shakeout time for all samples for the C.I composition under study. Increasing shake-out time decreased hardness and increased carbide grain size. Increasing silicon content was observed to increase grain size and reduce free graphite but with resultant decrease in hardness. Two mathematical relationships were derived. One related grain-size to silicon content and shakeout time while the second related Brinnel Hardness to Silicon content and shake-out time. They are: Grain Size=0.40 Si+0.17Shake-out Time-0.15 and BHN=-60.53Si-7.15Shake-out Time+329.35 at 1400℃ pouring temperature in a molding sand of specified properties and sand mould ambient temperature of 32℃.
文摘Casting simulation tool ADSTEFAN is useful to design casting technology of complicated iron castings.Based on the function of solidification analysis,special methods were taken to carry out the prediction and optimization of shake-out timing for large sized iron castings.It has been proved that these analyses are effective to iron casting production.During the research of cast iron semi-solid process,to predict and control the influence of inclined cooling plate on flow and heat transmission of molten iron,the basis of analysis model has been built in this study.Flow field simulation considering temperature field was carried out for further research and satisfied with the practical production.
