Method for solid state additive manufacturing
A method for forming an impact weld used in an additive manufacturing process. The method includes providing a wire having a powder filler metal core located within a sheath. The wire is then inserted within a conduit having an opening. Further, the method includes providing at least one energy pulse that interacts with the sheath to pinch off at least one segment of the wire, wherein the energy pulse causes propulsion of the segment toward a substrate with sufficient velocity to form an impact weld for welding the metal core to the substrate. In particular, the energy pulse is an electromagnetic pulse, a laser energy pulse or a high electric current pulse.
1. A method for forming an impact weld used in an additive manufacturing process, comprising:
providing a wire having a powder filler metal core located within a sheath, the sheath having electrically conductive properties;
inserting the wire within a conduit; the conduit having a circular opening forming a passageway penetrating through the side wall of the conduit;
providing at least one electromagnetic pulse through the circular opening, wherein the electromagnetic pulse interacts with the sheath causing the sheath to rupture pinching off at least one segment of the wire, wherein the electromagnetic pulse propels the segment toward a substrate with a velocity to form an impact weld for welding the powder filler metal core and the sheath to the substrate,
wherein the circular opening exposes a circumferential portion of the sheath.
2. The method according to claim 1 , wherein the circular opening is oriented transverse to an axis of the conduit.
3. The method according to claim 1 , wherein the sheath includes a flashing of copper.
4. The method according to claim 1 , wherein a plurality of segments are continuously deposited on the substrate to form a plurality of layers on the substrate.
5. The method according to claim 1 , wherein the circular opening and substrate are separated by a standoff distance to enable the segment to achieve the velocity for forming the impact weld.
6. The method according to claim 1 , further including:
providing first and second electrically conductive rails that receive the segment;
providing a pulse of high direct current that flows through the first electrically conductive rail, the segment and the second electrically conductive rail to propel the segment toward the substrate.
7. A method for forming an impact weld used in an additive manufacturing process, comprising:
providing a wire having a powder filler metal core located within a sheath, the sheath having electrically conductive properties;
inserting the wire within a conduit; the conduit having a circular opening forming a passageway penetrating through the side wall of the conduit;
providing at least one laser energy pulse through the circular opening, wherein the laser energy pulse interacts with the sheath to ablate the sheath and pinch off at least one segment of the wire, wherein the ablation generates gas pressure that propels the segment toward a substrate with sufficient velocity to form an impact weld for welding the metal core to the substrate, wherein the circular opening exposes a circumferential portion of the sheath.
8. The method according to claim 7 , wherein a portion of the laser energy pulse is directed toward a downstream end of the conduit to assist in propelling the segment.