Study on measurement of cooling process in molten pool of CO2 laser melt hardening

In order to study temperature field distribution in laser melt hardening,a non-destructive direct measurement method was developed.A novel laser molten pool dynamic process measurement system was set up.Thermal radiation image in laser melt hardening molten pool was captured at real time.Temperature field data at different time were obtained by theory analysis and experiment measurement.It is shown cooling process in molten pool includes solidification and temperature declining after solidification.Melting time,solidification time,temperature field distribution and molten pool size could be measured.These information could be used to optimize laser melt hardening process parameters.