High-strength and highly fatigue-resistant steel rail and production method thereof

Abstract

The present invention relates to a high-strength, highly wear-resistant, and highly contact-fatigue-resistant steel rail and a production method thereof, and belongs to the field of black steel manufacturing technology. The present invention provides a high-strength and highly fatigue-resistant steel rail, comprising the following chemical components by weight percentage: C: 0.76%˜0.86%; Si: 0.6%˜1%; Mn: 0.7%˜1.5%, Cr: 0.1%˜0.5%, and 0.8%≦Mn %+Cr %≦1.6%; V: 0.05%˜0.3%, Ni: 0.1%˜0.35%, and 0.15%≦V %+Ni %≦0.4%; Mo: ≦0.03%; P: ≦0.02%; S: ≦0.015%; Fe and inevitable impurities: the remaining content, wherein, the metallurgical structure of the steel rail is fine pearlite+A, where, A is proeutectoid ferrite or proeutectoid cementite, and A≦2%. The tensile strength of the obtained steel rail is 1,260 MPa˜1,420 MPa.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority to Chinese Application No. 201510006016.8, filed on Jan. 7, 2015, entitled “High-Strength and Highly Fatigue-Resistant Steel Rail and Production Method Thereof”, which is specifically and entirely incorporated by reference.FIELD OF THE INVENTION[0002]The present invention relates to a high-strength, highly wear-resistant, and highly contact-fatigue-resistant steel rail and a production method thereof, and belongs to the field of black steel manufacturing technology.BACKGROUND OF THE INVENTION[0003]With the rapid development of China's heavy haul railways, the axle load on the freight railways in China has been increased continuously. For example, the axle load on most mixed passenger and freight transport railways is 21 tons or 23 tons, the axle load on special major freight railways, such as Daqin Railway and Shuohuang Railway, is 25 tons, and the axle load on the South Central Channel, which has just be ...

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Benefits of technology

[0015]The technical problem to be solved in the present invention is to provide a high-strength, highly wear-resistant, and highly contact-fatigue-resistant steel rail and a production method thereof.

[0023]The present invention has the following beneficial effects. Compared with the inventions reported in the prior art, in the present invention, the second-phase structure (e.g., proeutectoid ferrite and proeutectoid cementite) is less, and the full rail profile is pearlite structure; especially, there is no martensite or bainite structure in tempered state in the rail web; thus, the risk of occurrence of horizontal cracks in the rail web in the service life of the steel rail is avoided. In addition, the present invention has the following advantages.

[0024](1) The production process of the steel rail is compact and the operation is easier to control; a secondary heating procedure is eliminated, when compared with an offline heat treatment process; thus, energy and production time are saved.

[0025](2) Through the process described above, the cooling of the rail head is more uniform, and the depth of hardened layer in the rail head is greater.

Problems solved by technology

In addition, as the axle load on freight railways is increased continuously, the need for high wear resistance performance and high contact fatigue resistance performance of freight railways becomes more urgent.

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