High-performance granular bainite rail steel and production process

Abstract

The invention relates to high-performance granular bainite rail steel and a production process, belonging to the technical field of metallurgical manufacturing. The high-performance granular bainite rail steel comprises the following raw materials in proportion: 0.19-0.28% of C, 1.20-1.70% of Si, 1.60-2.20% of Mn, 0.40-0.80% of Ni, 0.45-0.80% of Mo, not more than 0.018% of P, not more than 0.01% of S, not more than 0.20% of Cu, 1.20-1.80% of Cr, 0.04-0.18% of V and 92.362-95.02% of ingot iron. The production process of the high-performance granular bainite rail steel comprises the following steps of: (1) smelting at intermediate frequency to prepare electrode ingots; (2) remelting electroslag to prepare electroslag ingots; (3) carrying out hydrogen expansion on forgings; and (4) normalizing and tempering the forgings. The high-performance granular bainite rail steel has the advantages of reasonable proportion of chemical components, low manufacturing cost, good alloying effect, large forging ration change and favorable density of metal tissues; and each performance index of the product reaches or exceeds the levels of like products at home and abroad.

Description

technical field [0001] The invention belongs to the field of metallurgical manufacturing technology. Background technique [0002] With the development of the world economy, especially the rapid development of the domestic economy, the population flow and cargo turnover have risen sharply, which puts forward higher requirements for the railway trains that undertake more than 60% of the transportation tasks. In order to meet the needs of the rapid development of the domestic economy, our country has carried out six major speed increases in recent years. Recently, the country has established a medium and long-term strategic goal and plan for vigorously developing high-speed railways. However, with the increase of train speed, it is necessary It will bring greater inertia and produce greater impact and turbulence. In order to ensure the safety and reliability of high-speed trains, this puts forward higher requirements for frog rails. [0003] The current domestic frog is a who...

AI Technical Summary

Problems solved by technology

[0010] The purpose of the present invention is to provide a high-performance granular bainite core rail steel and its production process. The present invention adds an electroslag remelting (refining) process, adopts an advanced hydrogen expansion process and a normal tempering process, and obtains a good High-performance granular bainite structure to solve the problems of unreasonable chemical composition ratio, poor alloying effect, poor structure density, coarse grain, looseness, pores and inclusions in the existing overall casting technology; large performance dispersion and low product grade , low service life, not suitable for the current needs of my country's railway transportation safety, high speed, heavy load, etc.