The Effects of Sintering Schedule on Alloy Powder ASC 100.29 Compacts Formed at Elevated Temperature

Abstract

This paper presents the outcomes of an experimental investigations on the effect of sintering schedule i.e. holding time and temperature to the final properties of alloy powder ASC 100.29 formed through uniaxial die compaction process at elevated temperature. A lab-scale powder compaction rig with uniaxial compression and installation of heater was designed and fabricated in order to produce green compact from powder mass at elevated temperature. Alloy powder ASC 100.29 (99.7 wt%) and lubricant, zinc stearate (0.3 wt%) were mixed mechanically for 30 min at a rotation of 30 rpm. The powder mass was compacted at 150°C via simultaneous upward and downward uniaxial compression load of 425 MPa. Defect-free green compacts were generated from the compaction and were subsequently sintered at 1000°C using a custom argon gas fired furnace at three different sintering rates, i.e., 5, 10 and 15°C/min for three holding times, i.e., 30, 60 and 90 min, respectively. The final products were characterized through their physical, electrical and mechanical properties and their microstructures evaluated. The results revealed that the sample sintered for a longer period of time, i.e. 90 minutes at the slowest sintering rate, i.e. 5°C/min obtained the better final characteristics.