Vanadium-chromium micro-alloyed superfine pearlite steel rail

Abstract

The invention relates to a steel rail, and in particular relates to a vanadium-chromium micro-alloyed superfine pearlite steel rail. The technical problem to be solved by the invention is to provide the vanadium-chromium micro-alloyed superfine pearlite steel rail. The vanadium-chromium micro-alloyed superfine pearlite steel rail comprises the following components in percentage by weight: 0.78-0.86% of C, 0.15-0.70% of Si, 0.4-1.20% of Mn, 0.3-0.8% of Cr, 0.04-0.12% of V and less than or equal to 0.01% of S. A production method of the vanadium-chromium micro-alloyed superfine pearlite steel rail comprises the following steps: applying a water-mist gas mixture to the rail head part of the steel rail with waste heat after finishing rolling, wherein the cooling rate is 4-8DEG C / s; applying compressed air when the surface layer temperature of the rail head is reduced to 500-550 DEG C at a cooling rate of 1.5-3.5DEG C / s; and performing air cooling to room temperature when the temperature is less than 400 DEG C. The steel rail disclosed by the invention has excellent wear-resistant performance and good contact fatigue resistance, and is suitable for road segments with too fast wear and prominent fatigue problems of heavy haul railways.

Description

technical field [0001] The invention relates to a steel rail, in particular to a vanadium-chromium micro-alloyed ultra-fine pearlite steel rail. Background technique [0002] The rapid development of railways has put forward higher requirements on the performance of rails. Railway rails are mainly divided into two types: pearlite type and bainite type. Among them, pearlitic rails are divided into hypoeutectoid, eutectoid and hypereutectoid according to the differences in line conditions. At present, my country's existing passenger and freight mixed railways and heavy-duty railways mainly use U75V, U78CrV, U77MnCr and other eutectoid and hypereutectoid pearlite hot-rolled and heat-treated steel rails, and high-speed railways mainly use U71Mn hot-rolled steel rails. The improvement of the comprehensive performance of pearlitic rail mainly adopts three methods: microalloying, heat treatment and alloying + heat treatment, and alloying + heat treatment is considered to be the mo...

AI Technical Summary

Problems solved by technology

However, the improvement of wear resistance will lead to the reduction of the contact fatigue resistance of the rail, and it is easy to produce black spots, oblique cracks, peeling off blocks and other damage during the service process, especially when the regular grinding of the rail cannot meet the requirements More obvious; based on the problem that the wear and fatigue properties of pearlitic rails cannot be satisfied at the same time, it is believed that the development of pearlitic rails is close to the limit

Images