Ultra-free-cutting stainless steel subjected to calcium-tellurium-rare earth composite treatment and preparation method thereof

Abstract

The invention relates to ultra-free-cutting stainless steel subjected to calcium tellurium rare earth composite treatment and a preparation method thereof. Every 100 parts of ultra-free-cutting stainless steel subjected to calcium tellurium rare earth composite treatment comprises the following raw materials in parts by weight: less than or equal to 0.08 part of C, less than or equal to 1.00 part of Si, less than or equal to 2.0 parts of Mn, less than or equal to 0.060 part of P, 0.25-0.35 part of S, 8.5-10.0 parts of Ni, 17.0-19.0 parts of Cr, 0.002-0.008 part of Ca, 0.003-0.015 part of Te (tellurium), 0.002-0.012 part of Re, and the balance of iron and other impurities. The preparation method comprises the steps that the waste stainless steel is sequentially subjected to electric arc furnace smelting, AOD refining, LF refining, continuous steel casting, blank rolling and surface treatment so as to obtain the stainless steel. According to the ultra-free-cutting stainless steel subjected to calcium tellurium rare earth composite treatment, sulfides of the stainless steel are dispersed and evenly distributed, the turning performance and the mechanical performance of the stainless steel are excellent, and meanwhile, the purposes of reducing the influence of the sulfides on the mechanical performance and improving the machinability are achieved; and in addition, according to the preparation method, by optimizing the smelting process, the yield of a final stainless steel product can reach 95% or above, and the stainless steel product possesses better mechanical performance.

Description

Technical field [0001] The present invention relates to the technical field of steel manufacturing, and more particularly to ultra-easy-cut stainless steel and preparation methods thereof in a calcium rare earth composite treatment. Background technique [0002] Stainless steel is widely used due to excellent corrosion resistance, better plasticity and processability, and is therefore widely used. At present, not only has large amounts of oil, chemical, ocean, and machinery, but also in terms of food, medical, electronics, office. It also occupies a very important position. However, the stainless steel is hardened, so that stainless steel is poor, so that the product has low precision, low degree of automation, and has increasing the amount of stainless steel, the automation and high product accuracy requirements of stainless steel products are increasing, so develop Super easy to cut stainless steel material is particularly necessary. [0003] Easy cutting stainless steel refers...

AI Technical Summary

Problems solved by technology

Judging from the raw material ratio of the above-mentioned free-cutting steel, a small amount of calcium and rare earth has a limited effect on the spheroidization of sulfide, so that the improvement of cutting performance is not obvious

At the same time, the smelting methods of electric arc furnace, induction furnace and converter are greatly affected by scrap steel, and are not suitable for melting alloy elements, which will easily affect the yield and mechanical properties of the produced stainless steel.

[0006] In summary, the existing free-cutting stainless steels add single or combined elements of tellurium (Te), calcium (Ca), tin (Sn), and rare earth (Re) to carbon steel to achieve the purpose of spheroidizing sulfide. However, these proportioning methods cannot achieve the purpose of reducing the influence of sulfide on mechanical properties and improving machinability at the same time.

At the same time, the existing preparation methods of free-cutting stainless steel will also affect the yield and mechanical properties of stainless steel, which needs to be improved

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