HIGH-TEMPERATURE LUBRICANT AND ITS USE IN HOT-FORMING OF HIGH-GRADE STEELS AND CARBON STEELS UNDER PRESSURE

摘要

The invention relates to a high-temperature lubricant for use in the hot-forming of high-grade steels and carbon steels, said lubricant containing graphite, organic aerating agents and inorganic parting agents. The invention also relates to the use of such a lubricant. The aim of the invention is to provide a high-temperature lubricant that can be used for a wide range of steel qualities for various wall thicknesses and extensions to be obtained by rolling and that is temperature-stable, allows uniform rolling results with varying wall thicknesses and/or steel qualities and does not lead to the undesired carburization of the rolling stock. For this purpose, the high-temperature lubricant according to the invention comprises at least the following components in weight percent, based on the solids content: (a) 40 to 90% by weight of graphite, (b) 2 to 50% by weight of organic aerating agents, (c) 5 to 50% by weight of inorganic parting agents, the organic aerating agent (b) being selected from the group consisting of melamine, melam, melem, melon, phosphate salts and polyphosphate salts of the aforementioned compounds having phosphate chain lengths in the range of n = 1 to 1000, reaction products and addition products of the aforementioned compounds with cyanuric acid or isocyanuric acid and mixtures thereof, and the inorganic parting agent (c) being a layered silicate or a mixture of layered silicates.