改善不锈轴承钢9Cr18共晶碳化物的工艺研究

Study on Process to Improve Eutectic Carbide of Stainless Bearing Steel 9Cr18

采用金相显微镜分析了30 t EAF-LF-VD-Φ200 mm电极-Φ360 mm ESR锭-120 mm×120 mm锻坯-Φ50 mm轧材的冶炼和加工工艺对不锈轴承钢9Cr18共晶碳化物的影响,结果表明,模铸电极浇注温度由1500~1510℃降至1485~1495℃,电渣重熔熔速由4.5 kg/min降至3.5 kg/min,增强电渣重熔冷却条件,可以有效减少冶炼过程中的共晶碳化物原始形成。采用锻透力强、大变形开坯,可使大颗粒碳化物破碎、减小颗粒尺寸,降低碳化物条带和网状聚集程度,能够有效改善不锈轴承钢共晶碳化物评级,减小碳化物颗粒尺寸。

The effect of smelting and processing technology of 30 t EAF-LF-VD-Φ200 mm electrode-Φ360 mm ESR ingot-120 mm×120 mm forging billet-Φ50 mm rolled bar on the eutectic carbide in stainless bearing steel 9Cr18 is analyzed by optical microscope.Tested results show that,reduce the molded electrode pouring temperature from 1500-1510℃to 1485-1495℃,reduce the ESR melting speed from 4.5 kg/min to 3.5 kg/min,strengthen the electroslag remelting cooling conditions can effectively reduce the eutectic carbide in the original form in process of smelting;and the large carbide particles can be broken,the particle size can be reduced,and the degree of carbide band and network aggregation can be reduced by the way of forging penetration and large deformation to effectively improve the eutectic carbide rating of stainless bearing steel and reduce the carbide particle size.