Process for the production of a patented steel wire; yarn and filament produced by it; filament-reinforced rubber and tire article

摘要

The present invention discloses a process for producing a patented steel wire having a microstructure which is essentially pearlite with a very fine lamellar spacing between carbide and ferrite platelets which has good ductility and which can be drawn to develop high tensile strength, said process comprising the steps of: (1) heating a steel wire to a temperature which is within the range of approximately 850 DEG C to about 1050 DEG C for a period of at least about 2 seconds; wherein said steel wire is comprised of a microalloyed high carbon steel which consists essentially of about 97.03 to about 98.925 weight percent iron, from about 0.72 to about 0.92 weight percent carbon, from about 0.3 to about 0.8 weight percent manganese, from about 0.05 to about 0.4 weight percent silicon, and from about 0.005 to about 0.85 weight percent of at least one member selected from the group consisting of chromium, vanadium, nickel, and boron, with the proviso that the total amount of silicon, manganese, chromium, vanadium, nickel, and boron in the microalloyed high carbon steel is within the range of about 0.7 to 0.9 weight percent; (2) continuously cooling the steel wire at a cooling rate of less than 100 DEG C per second until a transformation from austenite to pearlite begins; (3) allowing the transformation from austenite to pearlite to proceed with an increase in the wire temperature resulting from recalescence; and (4) cooling the patented steel wire to ambient temperature. to