Method and apparatus for producing free-form products

A method of producing products from a powdered base material, by means of free form fabrication, wherein the powder granules are bound together into a solid product in accordance with the following steps:

• a. deposition in layers of the powder in a container having a bottom which can be elevated and lowered;
• b. treatment in layers of selected portions of the powder in a predetermined pattern with at least one additive, which divides said layers into supporting portions and product portions:
• a first additive being of a type which in a subsequent unification process inactivates supporting portions, so that a binding together of the granules substantially is prevented or reduced in such a unification process and/or a second additive being of a type, which in a subsequent unification process, activates product portions, so that a binding together of the granules takes place in such a unification process;
• c. repeated deposition in layers until all layers or all layers in a group have been deposited and treated in accordance with step b, said base material of the product portions still being unbound;
• d. the layered material in the container being subjected to a unification process, wherein the base material of the product portions is unified into a solid body;
• and
• e. removing the product manufactured in this way from the container and cleaning the product from the base material of the supporting portions.