Cracking perception of machine components with sound emission during steel quenching

Quenching and tempering often represent a stage near the end of the manufacturing process of machine components. The purpose of selecting the most suitable quenching parameters and controlling the hardening process is to ensure the required hardness and the residual stresses of a machine part. This paper includes the investigation of certain acoustic events during quenching. The possibility of understanding the relation between a connection during sound emission with the wetting kinematic of the quenching agent and a heated specimen with other phenomena during quenching was examined. It was determined that acoustic signals could identify the suitability, i.e.; the quality of the quenching process to ensure better control of the process. The possibility of acoustic signals caused by workpiece deformation and crack formation due to high internal stresses were examined. A comparison of results shows that this possibility can lead to an applicability of controlling the hardening process and quality of steel parts.