Abstract
The present paper deals with the heat flow and solid-state phase transformations during the laser transformation hardening of hypoeutectoid steel. A finite-difference computer model was developed to analyze the changes with the time of heat flow, the carbon redistribution in austenite and the subsequent quenching to martensite during laser transformation hardening. The analyzed results were shown in the pseudocolor images on the display. Furthermore, experimental surface transformation hardening was carried out using a square beam of uniform energy distribution, and the results were in good agreement with the theoretical results obtained by the computer model. The transformation hardening process can be also simulated for any given hypoeutectoid steel under any laser irradiating condition. The computer model proposed in the present paper can be applied to determine theoretically the best combination of the process variables for the laser transformation hardening in advance.
