Screw element and method for additive manufacture

A process for manufacturing a screw element comprising a shaft with a bone thread and a longitudinal central axis extending along the shaft and thereby defining a distal and a proximal direction, and the screw element further comprises a head, and a neck area and a tool attachment point is provided in the head, wherein at least three cantilever elements are attached to a proximal end of the head and said cantilever elements extend in the proximal direction beyond the proximal end of the head and are positioned mainly along the longitudinal central axis, the process comprising, comprising the steps:

• a. providing raw material particles of a Ti6Al4V alloy;
• b. additive building of the screw element by means of a 3D printing process, which joins the raw material particles together in three dimensions;
• c. stress relief heat treating the screw element at a temperature of at least 500° C., but not greater than 840° C., with a hold time of at least one hour, but less than 6 hours;
• d. removing cantilever elements from a proximal head area;
• e. second heat treating the screw element;
• and,
• f. removing incompletely joined raw material particles.