MSSBAUER INVESTIGATION ON QUENCHED STRUCTURES OF 40CrNiMo STEEL

The martensite microstructure,amount of retained austenite and its carbon concentration inthe 40CrNiMo steel quenched at various conditions have been investigated by using trans-mission Mossbauer spectroscopy at room temperature.It was shown that high-temperaturequenching and thermomechanical quenching has little influence on amount of retainedaustenite,thus the toughening effect of quenching was attributed to bulk lath martensite andits refining.