The Effect of Carbides Orientation in NC11 Steel on Scratch Susceptibility of Die Inserts Used to Press Stampings for Refractory Shapes

Abstract

NC11 steel, in view of the specificity of its manufacturing process, is characterised with band-like orientation of carbides. Depending on the direction of cutting the material for the inserts out of commercially available steel products, carbide bands can be oriented in parallel or perpendicularly to the direction in which aggregate grains move in the process of pressing stampings. It has been found that in case of scratches made in direction perpendicular to carbide bands, depth of the scratches is less than this observed when scratches are made in direction coinciding with prevailing orientation of carbide precipitates.

Surface Remelting of Mold Inserts Made of NC11 Steel

“…The length of the carbides is from 2 μm, and can be as long as 120 μm. The structure of the matrix of NC11 includes 9% Cr, 87% Fe and 0.23% Mn [4]. The microstructure of the NC11 steel used for the purposes of the present study is shown in its initial state in Figure 1.…”

“…As a result of the excessive wear of mold inserts, stampings of refractory material are prone to cracking and become unfit for the next production stage (firing). In view of stoppages and costs due to press retooling and replacement of the inserts, it became necessary to look for a solution enabling the extension of the service life of the components [1][2][3][4][5][6][7][8].…”