READY-USE LOW-CARBON STEEL MECHANICAL COMPONENT FOR PLASTIC DEFORMATION AND METHOD FOR MAKING SAME

摘要

The invention concerns a mechanical component resulting from hot process or cold process deformation of a steel without quenching and tempering treatment subsequent to forming. The low-carbon steel from which it is derived enables in effect a bainitic or substantially bainitic structure to be obtained from core cooling which can be reduced to about 1 °C/s, and consisting therefor additionally to iron and the unavoidable residual impurities resulting from steel preparation, of: at least 0.02 to 0.15 % of carbon, 0.04 to 0.10 % of niobium, 0.001 to 0.005 % of boron, 0.10 to 0.35 % of molybdenum, 1.30 to 2.00 % of manganese, 0.15 to 1.30 % of silicon, at least 0.015 % of nitrogen associated with a titanium content of the order of 3.5 times said nitrogen content, 0.01 to 0.08 % of aluminium. The components produced exhibiting good machinability are preferably used for imparting fatigue strength to precision components with high characteristics, such as vehicle wheel swivel joints, links, screws and the like.