This work describes a study of laser direct metal deposition (LDMD), using a diode laser in pulsed (discontinuous beam) mode and a coaxial powder nozzle. An experimental study analyses the effect of pulse parameters on the microstructure of thin-wall Waspaloy (nickel superalloy) parts and a simple model is used to explain some of the trends seen. Findings indicate that varying pulse parameters is potentially a useful way of controlling laser deposited superalloy part properties.

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