Abstract: The invention provides a method of fabricating a steel part, the method comprising the steps of: preparing and casting a steel having the following composition in percentage by weight: 0.06%?C?0.25%; 0.5%?Mn?2%; traces?Si?3%; traces?Ni?4.5%; traces?Al?3%; traces?Cr?1.2%; traces?Mo?0.30%; traces?V?2%; traces?Cu?3.5%; and satisfying at least one of the following conditions: 0.5%?Cu?3.5%; 0.5%?V?2%: 2?Ni?4.5% and 1%?Al?2%; ?the remainder being iron and impurities resulting from preparation; hot deforming the cast steel at least once at a temperature in the range 1100° C. to 1300° C. in order to obtain a blank of the part; controlled cooling of the blank for the part in still air or forced air; and heating the steel to perform precipitation annealing before or after machining the part from said blank. The invention also provides a part obtained by the method.

Abstract: Steel for mechanical components, wherein the composition thereof is, in percentages by weight: 0.19%?C?0.25%; 1.1%?Mn?1.5%; 0.8%?Si?1.2%; 0.01%?S?0.09%; trace levels?P?0.025%; trace levels?Ni?0.25%; 1%?Cr?1.4%; 0.10%?Mo?0.25%; trace levels?Cu?0.30%; 0.010%?Al?0.045%; 0.010%?Nb?0.045%; 0.0130%?N?0.0300%; optionally trace levels?Bi?0.10% and/or trace levels?Pb?0.12% and/or trace levels?Te?0.015% and/or trace levels?Se?0.030% and/or trace levels?Ca?0.0050%; the balance being iron and impurities resulting from the production operation, the chemical composition being adjusted so that the mean values J3m, J11m, J15m and J25m for five Jominy tests are such that: ?=|J11m?J3m×14/22?J25m×8/22|?2.5 HRC; and ?=J3m?J15m?9 HRC. Method for producing a mechanical component using this steel and a mechanical component produced in this manner.

Abstract: The invention provides a method of fabricating a steel part by forging, the method being characterized by the following steps:

Abstract: The invention provides a method of fabricating a steel part, the method comprising the steps of: