AISI 4140 steel of medium hardenability, with notable mechanical properties, can be hardened by transformation to martensite and tempering, reaching 4140 steel hardness of up to 50 HRC, its machinability is acceptable, and it is used for mechanical support application, from mechanical parts of machinery even anchors in construction.
SAE/AISI 4140 Known for its medium hardenability, it is presented as a versatile and resistant 4140 steel, its chemical composition, in compliance with ASTM A 29 / A29M – 16, DIN 1.7225, and JIS SCM440, reveals a precise balance of elements such as carbon, chromium, and molybdenum, this 4140 steel is supplied in two conditions, annealed, with hardness of 190 HB, and pretempered (hardness of 4140T), with hardnesses between 248 and 301 HBN.
The mechanical properties of AISI 4140 are impressive, with a tensile strength ranging between 850 and 1,000 MPa and an elastic limit of 680 MPa, its elongation in 2.0″ reaches 12%, these values, although estimated, offer a general reference. about the mechanical characteristics of this 4140 steel. 4140 steel stands out for its hardening capacity through quenching and tempering, reaching 4140 steel hardnesses of up to 50 HRC.
It extends to various areas, from mechanical parts of machinery to anchors in construction, the machinability of SAE 4140 is acceptable, approximately 61% compared to AISI 1112. Another of its applications for AISI 4140 is used for machinery components such as axles, gears and bolts, it is used as a 4140 steel plate or 4140 hollow bar, its possibilities are diverse, its mechanical resistance makes it ideal to replace carbon steels in situations that demand greater robustness.
Although the welding process is not recommended due to the risk of fracture, recommendations are provided for those cases where it is necessary, and the heat treatment, whether complete annealing or hardening, is carefully detailed to ensure specific properties.
In summary, AISI 4140 emerges as a versatile, resistant option with wide applications, demonstrating its worth in environments that require high mechanical resistance and durability. Its ability to replace obsolete steels and the possibility of hardening make this 4140 steel an outstanding choice. in the industry.
