Channel-die compression at high temperature

A new high temperature channel-die compression equipment is introduced. It is designed to operate under inert atmosphere at constant strain rate. Its main characteristics are described and compared to those of a previous appliance based on different principles, and designed for tests up to 600 ° C [C. Maurice, J.H. Driver, Acta Metall. Mater. 41 (1993) 1653-1664]. Tests have been performed in the same conditions with both appliances. The stress-strain curves show good agreement, but the deformed samples have different shapes. This difference is explained with the help of a finite element analysis which indicates that the deformation is more homogeneous in the new appliance, where the walls are unconstrained in the vertical direction. The new equipment is currently used to investigate the microstructural evolution of beta quenched Zircaloy-4 up to 750 °C. Some results regarding stress-strain relationships of Zircaloy-4 and deformation heterogeneities of lamellar microstructures are provided; they illustrate the potentialities of this equipment for the simulation of industrial processes.