2541M/34CrNiMo6 is a low-alloy (chrome-nickel-molybdenum) quenched-and-tempered (QT) steel with medium carbon content. Machinability is for the most part enhanced through M-treatment. In comparison with QT-steels based on CrMo, the strength level for a given dimension is higher for 2541M/34CrNiMo6 at the same time as a good combination of strength and toughness is achievable to larger diameters.
Tibnor has chosen to stock QT-bars which conform to the requirements for hardness and strength in the (discontinued) Swedish standard 2541. For dimensions up to an including 100 mm, strength and hardness are lower than for steel 34CrNiMo6 in SS-EN ISO 683-2 but for larger diameters, these properties are either equivalent to or better than in this standard. In concurrence with 34CrNiMo6, the guaranteed levels for yield strength, tensile strength and hardness decrease as the dimension increases even if the levels are fixed over stipulated diameter intervals. At variance with 34CrNiMo6 in SS-EN ISO 683-2, the impact strength is guaranteed to 27J better at -20°C. For complete information on the mechanical properties which apply for a given bar dimension, please consult Tibnors Stålvalsguide or the data sheet for 2541M/34CrNiMo6.
In Tibnor’s stock-standard programme for 2541M, diameters >20 mm are peeled while dimensions 10-20 mm are cold drawn and the relevant standard is then SS-EN 10277 - 5 with conditions “+QT” and “+C” (cold-drawn). The cold-drawn diameter tolerance is h10 (ISO 286-2).
Welding of 2541M is not to be recommended. The steel is weldable but the procedure is complicated and time consuming. In addition, parts should preferably be quenched-and-tempered again after welding. Machining of
QT-steels is generally considered troublesome but there is a pronounced enhancement of machinability thanks to the M-treatment.
If the application requires a wear-resistant surface, 2541M responds well to surface hardening by both induction hardening and nitriding.