Free machining structural steel of containing stannum

Abstract

A Sn-contained structural steel easy to machine contains C, Si, Mn, Cr, S, P, Sn (0.09-0.25 wt.%), O and Fe. Its advantages are high machinability, and better mechanical performance including tension strength, plasticity, hardness, impact resistance, etc.

Description

Technical field [0001] The invention is a series of tin-containing free-cutting structural steels, which can replace lead-containing free-cutting steels and are widely used in the mechanical processing industry. The invention belongs to the technical field of iron-based alloys. Background technique [0002] Free-cutting steel is now mainly used in machinery manufacturing industries such as the automobile industry, instruments and meters, and standard parts. At present, the world's annual consumption has exceeded 4 million tons, half of which are produced by the United States and Japan. In 2000, my country's demand for free-cutting steel was about 400,000 to 500,000 tons, while my country's annual output was only more than 30,000 tons, which required a large amount of imports. With the development of my country's modern industry, the free-cutting steel market has great potential. [0003] The existing free-cutting steel varieties are mainly formed by adding free-cutting el...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to develop a series of high-performance tin-containing free-cutting structural steels to gradually replace the sulfur-containing free-cutting steels and lead-containing free-cutting steels widely used in the market, so as to overcome the inclusions of high-sulfur free-cutting steels Severe air pollution during smelting and the smelting and processing of lead-containing free-cutting steel and the problem that lead is likely to cause harm to the environment and human health during steel recycling