Wear-resistant steel plate for railcar turnout and production method thereof

Abstract

The invention provides a wear-resistant steel plate for a turnout of a tramcar and a production method thereof. The steel plate is prepared from the following components in percent by weight: 0.16-0.22% of C, 0.2-0.4% of Si, 0.60-1.00% of Mn, 0.6-1.0% of Cr, 0.2-0.4% of Mo, 0.015-0.03% of Nb, 0.4-0.6% of Ni, 0.0008-0.0022% of B, 0.10-0.20% of Ti, 0.015-0.045% of Als, less than or equal to 0.012% of P, less than or equal to 0.03% of S, less than or equal to 0.0040% of [N], less than or equal to 0.00015% of [H], less than or equal to 0.0020% of [O] and the balance Fe and inevitable impurities. The production method comprises the following steps: smelting; continuous casting; slab stacking and slow cooling; cleaning at temperature; slab heating; controlled rolling; straightening; steel platestacking; and thermal treatment. The steel plate is simple in chemical component, and the carbon equivalent is 0.5-0.63, so that smelting and welding are facilitated; tempering heat treatment is not needed, the surface hardness is greater than 370 HB, the section hardness is uniform, and the low-temperature toughness at 40 DEG C below zero is greater than 30 J.

Description

technical field [0001] The invention belongs to the field of metal materials, in particular to a wear-resistant steel plate for a railcar turnout. Background technique [0002] Compared with the subway, the modern tram has the advantages of small investment, short construction period, various line forms, and flexible design; the tram switch is mainly used in the city due to the environmental requirements, and the design needs to achieve high precision, low noise, and high comfort. . [0003] In order to facilitate maintenance, replacement and reduce the cost of the early tramway switches in our country, most of them were produced with high manganese steel monolithic frogs. The internal defects of the switches, such as porosity, shrinkage porosity, and micro cracks, were serious, and horizontal cracks and cracks were easily generated during use. Vertical cracks, and because the weight of the tram is light and the running speed is not fast, the impact force on the surface of ...

AI Technical Summary

Problems solved by technology

Its disadvantage is that the invention is designed with high manganese steel composition, which is not suitable for the use of tramway switch with low impact load

Its shortcoming is, this invention C and Cr, W, Ni content are high, and cost is high, can't be welded, can only adopt the method for casting

Its shortcoming is that this invention is rolled turnout section steel, and carbon equivalent is high, and contains higher Si and carbon and Cr, Mo alloy, and cost is high, is difficult for welding, and after rolling, segmental controlled cooling is needed to realize ideal Performance, complex production process

Its disadvantages are that the content of Cu, Cr, Mo, W and other alloys is high, the cost is high, continuous casting is difficult, it is not easy to weld, and the secondary quenching heat treatment process is complicated

[0014] 1. It is produced by high manganese steel casting, with many internal defects and poor wear resistance;

[0015] 2. It is produced by rolling section steel, with high carbon and carbon equivalent, and poor weldability;

[0016] 3. It is impossible to meet the requirements of steel plates for welded turnouts with a thickness of more than 80mm;

[0017] 4. The production process is complicated, tempering or slow cooling is required, and delayed cracks are prone to appear

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