Method and device for manufacturing titanium objects

A reactor for production of an object of a weldable material by solid freeform fabrication, where the reactor comprises:

• a reactor chamber (1), which is closed to the ambient atmosphere, wherein the reactor chamber (1) is filled with argon as an inert gas,
• an actuator (2) controlling the position and movement of a support substrate (3) placed inside the reactor chamber (1),
• an actuator (4) controlling the position and movement of a high energy plasma transferred arc welding torch (5) with a wire feeder,
• a control system able to read a virtual three dimensional vectorized layered model of the object which is to be formed and employ the virtual model to control the position and movement of the actuators (2, 4), operation of the welding torch (5) and wire feeder such that a physical object is built by welding a layered structure of quasi one-dimensional pieces of the weldable material onto the supporting structure according to the virtual three dimensional vectorized layered model of the object which is to be formed,
• characterized in that
• all adjacent wall elements (6) of the walls of the reactor chamber are joined with an obtuse angle, the actuator (2) extends from below the reactor chamber (1) and protrudes into the reactor chamber (1) through a first opening (7) in the reactor chamber (1) wall holding the support substrate (3) inside the reactor chamber (1),
• the first opening (7) is sealed by at least one elastic gas impermeable membrane (8), which is gas tight attached to the reactor wall at the first opening (7) and to the actuator (2),
• the actuator (4) extends from the outside of the reactor chamber (1) and protrudes into the reactor chamber (1) through a second opening (9) of the wall of reactor chamber (1) holding the high energy plasma transferred arc welding torch (5) with wire feeder of the weldable material inside the reactor chamber (1),
• the second opening (9) is sealed by the at least one elastic gas impermeable membrane (10), which is gas tight attached to the reactor wall at the second opening (9) and to the actuator (4), and
• the reactor is equipped with at least one closable gas inlet (11) located in the lower part of the reactor chamber (1) and at least one closable gas outlet (12) located at the upper part of the reactor chamber (1).