Characteristics of laser heat treating during processing of a low carbon steel

Some of the characteristics of laser heat treating are examined. A numerical model has been created that quantifies the transient thermal field to assist in the prediction of heating and cooling rates that influence the transformation from one solid phase to another. The model is compared to experiments performed on coupons of AISI 1050 steel with a Nd:YAG . By comparing experimental heat affected zone depths with corresponding modeled thermal fields, an estimate of the influence of heating rate on the temperature at which ferrite begins to transform to other phases is made. Bulk heating from repetitive tracks is seen to reduce cooling rates in subsequent processing tracks, though they remain high and the reduction is not likely to influence transformations that depend on high cooling rates (austenite to martensite for example).