Possibilities of a new cold upsetting method for increasing magnesium plastification

Resumo

A new cold deformation method of cast magnesium is proposed. The method includes the implementation of the upsetting technique under lateral pressure. The billet is initially placed into a jacket made of ductile metal and then into a container. The billet is affected with a puncheon placed into the container with a gap. Under the press force, the jacket metal flows into the gap and forms the pressure. This results in an increase in the level of compressing stresses, which increases the ductility of magnesium. Deformation tests of cast magnesium samples showed that the relative reduction without destruction can be increased from 12‒18 to 60–70%. Such an increase in ductility makes it possible to produce deformed magnesium billets without heating. A simplified removal procedure of the samples from jackets after the completion of deformation is foreseen. It is revealed that the process can be performed at average upsetting pressures of 820–830 MPa, which is acceptable for modern tool materials.