Process Optimization And Performance Stability Of GCr15 Steel

Bearing is the "industrial heart",which is widely used in various industries and is closely related to the development of national economy.In the meantime,bearing steel is a kind of alloy steel,its production difficulty is maximal,quality requirement is most strict.In production,the practical performance and fatigue life of steel for normative requirements of the process more strictly,mainly includes the following factors: the content of harmful impurity elements,non-metallic inclusion content and gas content uniformity,carbide,etc.The methods of improving the bearing steel in process of production is the common problem faced by every manufacturer.C content is 1.0%,Cr content is 1.5% of high carbon chromium bearing steel(GCr15)is the most representative of bearing steel,with the development of more than 100 years history,composition does not change,in the progress of metallurgical technology,its performance has been greatly improved.Based on the production background of GCr15 bearing steel and its wire,the production results of GCr15 bearing steel are mainly reflected in the following two parts:Produced in GCr15,preliminary set up production plan,The alloying elements in the chemical composition of GCr15 molten iron meet the actual production requirements,when the converter tapping carbon content meet the production requirements,but excess levels of P,in the process of refining,high FeO content,is not normal.The gas sample is not normal,O is not uniform.,the steel water can not guarantee normal pouring.Moreover,the surface quality of the cast billet is not good,and the surface has many defects such as longitudinal crack,angular crack,transverse crack and reticulate.In the metallographic photograph,the centre is heavily carbon.Therefore,the rolling wire has a lot of cracks and serious defects.Under the condition of the existing production process,from the determination of chemical composition of GCr15,molten steel cleanliness control,the control of carbon segregation and billet heating quality and control,control of rolling,“steel” main quality control factors such as the cooling is optimized,perfect,found through technology improvement,the chemical composition of the final products,gases and inclusions in steelin accordance with requirements,C slab center segregation index of 1.10 or less,carbide liquid chromatography were 100% qualified,achieved the goals and objectives,and the finished surface also not found crack defects,from the production process and finished product inspection data analysis and the usage of the user,The optimized process of GCr15 steel making and rolling steel is feasible and can achieve the desired goal.