FEASIBILITY OF METAL-FORMING IN SEMILIQUID STATE

The work described in this paper is connected with Authors' earlier re search on the formability of alloys in semi-liquid (partly liquid) sta te, i.e. at the temperatures exceeding their solidus points. Two alumi nium based alloys of a relatively large crystallization temperature ra nge have been used as the testing materials. The investigation focused on the effect of the liquid fraction (volume percentage of liquid com ponent in the alloy, pre-heated to the temperature above its solidus p oint) on the parameters of the plastic deformation. The process of ups etting of the cylindrical specimens is investigated. The prime objecti ve of the work is to determine the factors which affect the softening of various alloys subjected to deformation in semi-liquid state. An at tempt of the generalization of the problem is done. Thermal-mechanical finite element model developed for the compression process and adapte d to the semi-liquid conditions is used for the calculation of the def ormation parameters.