Q.What are the differences between extrusion and injection moldinding ?
A: Extrusion is done by pushing a pliable material (naturally or through heat) through a die (essentially a cut-out, simple or complex, in a solid material) so that lengths of the material take the form of the die. It can then be heat treated, cold worked, or cut as needed.
Injection molding begins with a mold (the three-dimensional form desired). Liquid silicone rubber or thermopalstics and thermosetting polymers, often in the form of pellets, are meltal and injected into the hollow space of the mold. Additionally, another mold may be inserted into the liquid to create hollow space and/or textures after cooling.