Layered manufacturing of single crystal alloy components

An apparatus for making a metallic component, comprising:

• a build enclosure configured to hold metallic powder of a predetermined composition;
• a directed energy source operable to produce an energy beam suitable for fusing the metallic powder;
• a beam steering apparatus operable to direct the energy beam over the metallic powder in a pattern corresponding to a cross-sectional layer of the component;
• an external heat control apparatus separate from the directed energy source, wherein the external heat control apparatus is operable to control both the temperature and the heating rate of the component during depositing and fusing of the metallic powder and to maintain a predetermined temperature profile within the build enclosure;
• and
• a retractable induction heater comprising an induction coil connected to an electric power source and mounted above the build enclosure by an arm connected to an actuator, wherein the actuator is operable to move the induction coil between an in-use position and a retracted position away from the build enclosure.