Metal Powder Extrusion of Magnetocaloric Heat Exchanger Structures

摘要

Metal Powder Extrusion is a very efficient method to produce complex-shaped components. Whenapplying the process to the production of magnetocaloric heat exchanger structures, both the oxygensensitivity of the magnetocaloric material (LaFeSi-based alloy) and the specifications regarding thegeometry (wall thickness <500 μm for optimized heat transfer) impose special challenges to theprocessing. The study describes the adjustment of the binder and feedstock composition, the tool designand the process parameters to meet these requirements and to assess the smallest wall thicknessattainable. The dimensional accuracy, the oxygen and carbon content and the magnetocaloricproperties after extrusion, subsequent debinding and sintering are examined.