Effect of soft blowing on the purity of GCr15 bearing steel
Using high-quality GCr15 bearing steel as the research object,a comparative study was conducted on the T.O content and inclusion evolution law in bearing steel under different bottom blowing argon flow rates and different soft blowing treatment times during RH refining process using ASPEX automatic scanning electron microscopy and oxygen nitrogen analyzer.The results show that,the flow rates of bottom blown argon and soft blowing time have no effect on the evolution of inclusion types.The main types of inclusions before and after soft blowing are Al2O3-CaO,Al2O3-MgO-CaO,and Al2O3-MgO-MnS composite inclusions.Soft blowing has a significant removal effect on inclusions and T.O content.From the beginning to the end of soft blowing,the mass fraction of total oxygen in the steel decreases by 6× 10-6,the inclusion area fraction increases from 0.041 9％at the beginning of soft blowing drops to 0.022％,inclusion particles with dimensions exceeding 20 μm float faster and are easier to remove.The flow rate of bottom blown argon has a significant impact on the removal of inclusions.As the bottom blown flow rate increases from 30 L/min to 100 L/min,the average removal rate of inclusions decreases from 47％to 40％.
soft blowing timeinclusion number densityinclusion area fractionremoval rate
万方数据
维普
