A wire dispenser for a laser metal wire deposition machine, the wire dispenser comprising: a longitudinal duct for guiding a wire from a proximal end to a distal end of the duct; and a nozzle unit comprising a metal nozzle and a thermal control device, the metal nozzle being connected to the distal end of the duct and having a through bore for receiving the wire from the distal end of the duct and for discharging the wire adjacent to a laser metal wire deposition site; characterized in that: the thermal control device includes a metal front block positioned laterally of a front portion of the through bore of the nozzle and a rear cooling portion positioned laterally of a rear portion of the through bore of the nozzle and rearwardly of the front block; the rear cooling portion of the thermal control device contains a cooling circuit for a cooling liquid; the metal front block and the rear cooling portion form a sleeve-like device which is removably fitted onto the metal nozzle; the nozzle is of a replaceable type which is removable from the distal end of the duct; the thermal control device has a sleeve bore extending from a rear face of the rear cooling portion to a front face of the front block and the nozzle is seated in the sleeve bore; and the longitudinal position of the nozzle in the sleeve bore is such that a front tip of the nozzle is within a range of plus 1mm to minus 5mm of the front face of the front block. a longitudinal duct for guiding a wire from a proximal end to a distal end of the duct; and a nozzle unit comprising a metal nozzle and a thermal control device, the metal nozzle being connected to the distal end of the duct and having a through bore for receiving the wire from the distal end of the duct and for discharging the wire adjacent to a laser metal wire deposition site; characterized in that: the thermal control device includes a metal front block positioned laterally of a front portion of the through bore of the nozzle and a rear cooling portion positioned laterally of a rear portion of the through bore of the nozzle and rearwardly of the front block; the rear cooling portion of the thermal control device contains a cooling circuit for a cooling liquid; the metal front block and the rear cooling portion form a sleeve-like device which is removably fitted onto the metal nozzle; the nozzle is of a replaceable type which is removable from the distal end of the duct; the thermal control device has a sleeve bore extending from a rear face of the rear cooling portion to a front face of the front block and the nozzle is seated in the sleeve bore; and the longitudinal position of the nozzle in the sleeve bore is such that a front tip of the nozzle is within a range of plus 1mm to minus 5mm of the front face of the front block. the thermal control device includes a metal front block positioned laterally of a front portion of the through bore of the nozzle and a rear cooling portion positioned laterally of a rear portion of the through bore of the nozzle and rearwardly of the front block; the rear cooling portion of the thermal control device contains a cooling circuit for a cooling liquid; the metal front block and the rear cooling portion form a sleeve-like device which is removably fitted onto the metal nozzle; the nozzle is of a replaceable type which is removable from the distal end of the duct; the thermal control device has a sleeve bore extending from a rear face of the rear cooling portion to a front face of the front block and the nozzle is seated in the sleeve bore; and the longitudinal position of the nozzle in the sleeve bore is such that a front tip of the nozzle is within a range of plus 1mm to minus 5mm of the front face of the front block.