Variation in pore distribution along sample length in sintered 7xxx aluminum alloy
(1. Research Institute, Baoshan Iron & Steel Co., Ltd., Shanghai 201900, China;
2. State Key Laboratory of Development and Application Technology of Automotive Steels (BaoSteel),
Shanghai 201900, China;
3. School of Mechanical and Mining Engineering, the University of Queensland, Queensland 4072, Australia)
2. State Key Laboratory of Development and Application Technology of Automotive Steels (BaoSteel),
Shanghai 201900, China;
3. School of Mechanical and Mining Engineering, the University of Queensland, Queensland 4072, Australia)
Abstract: An experimental and computational fluid dynamics (CFD) numerical study of the sintering of an Al-7Zn-2.5Mg-1Cu alloy in flowing nitrogen was presented. Three rectangular bars with dimensions of 56 mm × 10 mm × 4.5 mm each, equally spaced 2 or 10 mm apart, were sintered in one batch at 620 °C for 40 min in a tube furnace. The pore distribution in the selected cross section of sintered samples was found to be dependent on the sample separation distance and the distance from the cross section examined to the sample end. A three-dimensional (3D) CFD model was developed to investigate the nitrogen gas behavior near each sintering surface of the three samples during isothermal sintering. The variation in porosity in the cross section of each sintered sample along sample length was found to be closely related to the nitrogen gas flow field near the sintering surfaces.
Key words: aluminum alloy; sintering; pore distribution; nitrogen; computational fluid dynamics (CFD) modeling