Sintering of FeCuAl powder compacts formed through die compaction process at elevated temperature

Abstract

This paper presents the outcomes of an experimental investigation regarding the sintering characteristics of FeCuAl powder compacts formed through uniaxial die compaction process at elevated temperature. A lab-scale uniaxial die compaction rig was designed and fabricated in order to shape powder mass at elevated temperature. Iron powder ASC 100.29 (92 wt%) was blended mechanically together with other elemental powders, i.e., copper (7.5 wt%), and aluminum (0.5 wt%) at a rotation of 30 rpm for 30 min. The prepared feedstock was shaped at 200°C through simultaneous upward and downward axial loadings of 325 MPa and the product generated through this process is known as green compacts. The defect-free green compacts were subsequently sintered in argon gas fired furnace at constant temperature, i.e., 800°C at three different sintering rates, i.e., 5, 10 and 15°C/min for three different holding times, i.e., 30, 60 and 90 min, respectively. The final products were then characterized for their physical, electrical, and mechanical properties and their microstructures were evaluated. The results revealed that the sample sintered for a shorter period of time, i.e., 30 min at a moderate heating/cooling rate, i.e., 10°C/min obtained the better final characteristics, i.e., higher relative density, lower volumetric expansion, lower electrical resistivity, higher strength and more uniform microstructure.