Abstract：Through the macroscopic examination, metallographic examination and determination of ductile brittle transition temperature of the transverse crack defect sample of 430 stainless steel continuous casting slab, it determined that a large amount of precipitation of carbide in ferrite grain boundary accelerated the propagation of the crack in slab, which can make the brittle fracture happen more easily. Corresponding control measures were proposed,including improving the arc alignment precision of casting machine, making the arc alignment precision of the export of foot roller,zero period and first period equal to 0.5mm,0.33mm and 0.27mm,respectively, controlling the temperature of slab fast cooling in the vicinity of 500℃to avoid brittle phase,making the total content of C and N less than 0.03%, and ensuring the grinding temperature over 120℃as well as completing the turn sequence and rolling of casting slab within one week. Industrial test was carried out on the optimized process.It concluded that the transverse crack defects in 430 slab had been effectively controlled, which can eliminate the heat strip breaking accident and steel belt hole defects caused by transverse crack of slab.The effect of the process measures was remarkable.
2015, Vol. 25 
