Production technology of low-phosphorous stainless steel

Abstract

The invention relates to the technical field of metal smelting, and provides a production technology of low-phosphorous stainless steel. The production technology of the low-phosphorous stainless steel comprises the steps that solid metal is placed into a non-vacuum induction furnace to be melted, and the carbon content in obtained molten steel is adjusted to be greater than or equals to 1.0%; themolten steel is blended into an AOD furnace to be blown, and the blowing temperature is controlled at 1550 DEG C-1600 DEG C; slag making materials are added into the molten steel for slagging in theblowing process, and the target alkalinity is 3.5-4.5; gas of oxygen and nitrogen is mixed for blowing, and the gas flow is controlled to 800-1000m<3>/h; blowing is stopped after 40-50 minutes of blowing, and the phosphorus content in the molten steel is analyzed by sampling; and when the phosphorus content is less than or equals to 0.003%, oxidizing slag in the furnace is removed, and then conventional smelting is carried out on the obtained low-phosphorus molten steel. The phosphorus content in the obtained stainless steel is lower than 0.015%, and production of stainless steel such as nuclear power and chemical industry is met. Compared to a traditional dephosphorization technology, the production technology of the low-phosphorous stainless steel greatly saves energy consumption and reduces production cost, and the dephosphorization efficiency is high.

Description

technical field [0001] The invention belongs to the technical field of metal material smelting, and in particular relates to a production process of low-phosphorus stainless steel. Background technique [0002] At present, my country's stainless steel industry is developing rapidly, but the main products are still concentrated in low-end fields such as rods and wires, pipes, etc. Some high-quality materials and high-end products still rely on imports. There are strict requirements for impurities and harmful elements in the steel, such as urea grade and nitric acid grade stainless steel, which require P≦0.015% in steel, and steel for high-end petrochemical gas pipelines also requires phosphorus content below 0.015%, in order to improve the performance of steel , the latest research results show that reducing the phosphorus content in steel can improve the corrosion resistance of stainless steel and play an important role in improving the service life of chemical and petrochemic...

AI Technical Summary

Problems solved by technology

[0003] At present, the control of phosphorus content in domestic stainless steel production is mainly realized by low-phosphorus raw materials. Domestic enterprises such as Tsingshan Stainless Steel and Yongxing Special Steel all use low-phosphorus ferronickel (or molten nickel-iron) to control the phosphorus content in steel. Taiyuan Iron and Steel and Baosteel do not Rust and other large-scale enterprises use molten iron dephosphorization