RU2003110866A - METHOD FOR PRODUCING FROM CONTINUOUS BARING OF VARIETIES WITH SPHEROIDIZED STRUCTURE FROM BORN-CONTAINING STEEL FOR COLD VOLUME STAMPING OF HIGH-STRENGTH FASTENING PARTS - Google Patents

Claims (6)

1. Method for the production of long products from boron-containing steel for cold forging of high-strength fasteners, including steelmaking in an electric furnace, out-of-furnace treatment, microalloying with boron in a vacuum generator, continuous casting on high-speed continuous casting machines with argon protection, hot rolling of continuously cast billets using controlled rolling modes and winding long products into riots followed by accelerated spheroidizing annealing, including high-speed induction heating in intercritical the temperature shaft of cold-deformed metal with subsequent regulated cooling in the temperature range 650-730 ° C, with speeds of 0.5-1.0 ° C / min, characterized in that the steel is smelted containing wt.%: Carbon, Silicon, Manganese, Chromium, Boron, Aluminum , Titanium, Nitrogen, Sulfur, Calcium, Iron, the rest in the following ratio of components, wt.%: Carbon 0.17-0.34 Manganese 0.90-1.40 Silicon 0.01-0.20 Chrome 0.005-0.40 Boron 0.0005-0.0050 Titanium 0.01-0.04 Sulfur 0.005-0.020 Aluminum 0.02-0.06 Calcium, 0.001-0.010 Nitrogen 0.005-0.015 moreover

2. The method according to claim 1, characterized in that the use of deoxidizers and alloys with a low nitrogen content. 3. The method according to any one of claims 1 or 2, during continuous casting use protection of the jet from contact with air. 4. The method according to any one of claims 1 to 3, characterized in that the doping with boron is carried out in a vacuum. 5. The method according to any one of claims 1 to 4, characterized in that the hot rolling starts at a temperature of 900-950 ° C and ends at 740-850 ° C, with a deformation in the last passes of at least 20%. 6. The method according to any one of claims 1 to 5, characterized in that the spheroidizing annealing does not require preliminary cold deformation of the rolled product and involves rapid heating in the temperature range (A _Cl + 10-30 ° C), followed by regulated cooling in the temperature range 650- 730 ° C, with speeds of 0.5-1.0 ° C / min and further cooling in a heat chamber at an ambient temperature of -100-200 ° C.