STEEL FOR BALL-CAGE TYPE UNIVERSAL JOINT RETAINER AND PRODUCTION METHOD THEREFOR

The present invention belongs to the technical field of special steel smelting, and relates to a steel for a ball-cage type universal joint retainer and a production method therefor. The steel comprises the following chemical ingredients by wt%: 0.10 - 0.25% of C, 0.20 - 0.40% of Si, 0.40 - 0.65% of Mn, 0.40 - 0.70% of Cr, 0.0003 - 0.0025% of B, 0.010 - 0.035% of Ti, 0.30 - 0.45% of Mo, 0.0050 - 0.0100% of N, ≤ 0.015% of S, ≤ 0.025% of P, ≤ 0.25% of Ni, ≤ 0.30% of Cu, 0.015 - 0.035% of Al, ≤ 0.0010% of O,≤ 0.04% of As,≤ 0.03% of Sn, ≤ 0.005% of Sb, ≤ 0.002% of Pb, and the balance being Fe and unavoidable impurities. The microstructure of the steel is bainite, and the grain size of austenite is larger than or equal to 6 grades. The production process comprises primary smelting of molten steel, refining of molten steel, vacuum degassing of molten steel, continuous casting, hot rolling and finishing. In the present application, the chemical ingredients are optimized, and the alloy costs are reduced. Furthermore,