Graphite-containing high-speed steel roller

Abstract

The invention discloses a graphite-containing high-speed steel roller and belongs to the field of mechanical casting. B and N chemical elements are introduced into traditional high-speed steel components; MC-type and / or M<2>C-type, and dot-shaped and / or blocky highly-hard alloy carbides, nitrides and borides with the total area percentage being 20-35% are dispersed and distributed in a matrix structure of a working layer; the two steps that firstly, carbide, nitride and boride modification treatment is performed, and then graphite modification inoculation treatment is performed are adopted, graphite is separated out of an original structure, therefore, the high-speed steel roller maintains the unique advantage of high temperature abrasion resistance of traditional high-speed steel, meanwhile, the problem of a large friction coefficient of original traditional high-speed steel rollers is solved, the abrasion resistance of high-speed steel is fully achieved, the lubrication effect between the roller and a workpiece during rolling is achieved, and therefore, occurrence of the steel-adhesion phenomenon is prevented; and besides, by means of heat-conducting property and lubricating property of graphite, the defects of thermal impact, hot cracking sensitivity, steel adhesion tendency and surface texturing tendency of the high-speed steel rollers can be overcome, and especially during usage for a finished product rack, the surface brightness of rolled products is improved remarkably.

Description

technical field

[0001] The invention relates to a graphite-containing high-speed steel roll, which belongs to the field of mechanical casting. Background technique

[0002] The alloy content of the outer layer (working layer) of the existing traditional high-speed steel roll is usually C 1.5-2.5, Si 0.2-0.8, Mn 0.4-0.8, P≤0.05, S≤0.02, Cr 4-6, Ni 0.6- 1.5, Mo 3-5, W 0-3, the metallographic structure of the outer layer does not contain graphite, and these alloy elements mainly exist in the form of carbides in the roll structure, and the proportion of carbides is usually 10-20% between. The proportion of granular alloy carbides is relatively low, and the proportion of matrix area is relatively large. Therefore, during the use of the roll, especially when it is used for the finish rolling product stand, the rolling temperature is low, and the rolling speed is high, the roll base is exposed to the rolling material passing through at low temperature and high speed and the entra...

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