Gravitational Effects on Compact Shaping and Microstructure during Supersolidus Liquid Phase Sintering of Cu-10Sn-10Pb

Authors

• M. Mousapour
• M. Azadbeh
• M. Ojaghi

Abstract

With increasing sintering temperature, liquid is pulled down by gravity and it causes porosity elimination at this area. The difference in liquid volume fraction makes microstructural gradient from up to bottom of sintered compacts. In this paper the influence of gravity on shape and also microstructure evolution of compacts was studied. Cu-10Sn-10Pb samples were sintered at the range of 890-970°C for 20 min. The in situ images from samples were taken at various sintering conditions. It is concluded that distortion increases from top to bottom sections of samples due to viscosity reduction and the weight of upper sections. Liquid volume fraction at the bottom increases with increasing sintering temperature and finally elephant foot profile is appeared. Lead plays an important role in fragmentation and rearrangement of bronze particles and this affects on shape and microstructure during sintering.

Keywords

• Supersolidus sintering
• Gravity
• Microstructural gradient
• Viscosity
• Elephant foot

---

References

1- R. M. German, "Supersolidus Liquid Phase Sintering of Prealloyed Powders", Metallurgical and Materials Transactions A, Vol. 28, PP. 1553-1567, 1997.

2-Y. Liu, R. Tandon  R. M. German, "Modeling of Supersolidus Liquid Phase Sintering, Part. I: Capillary Force", Metallurgical and Materials Transactions A, Vol. 26 (A), PP. 2415-2422, 1995.

3- م. قارونی جعفری، م. آزادبه،” مطالعه تغییرات ریزساختاری در تف جوشی سوپرسالیدوس آلیاژ برنجی “Cu-28Zn، مجله مواد نوین، جلد 3، شماره 2، 1391.

4-ا. محمدزاده، م. آزادبه،” مدل سازی و بررسی تاثیر متغیرهای تفجوشی فاز مایع سوپرسالیدوس بر خواص فیزیکی و مکانیکی آلیاژ“Cu-28Zn، مجله مواد نوین، جلد 3، شماره 3، 1392.

5-م. آزادبه، ع. صباحی نمین، ا. محمدزاده، ح. شفیعی،” بررسی تاثیر تفجوشی در فاز مایع بر چگالش و ریزساختار آلیاژ “Cu-xZn، مجله مواد نوین، جلد 3، شماره 4، 1392.

6-ش. شادپور، م. آزادبه، ع. صباحی، " بررسی
تغییرات ریزساختاری و ابعادی آلیاژ برنز سرب­دار تف­جوشی شده در حضور فاز مایع"، چهارمین همایش مشترک انجمن مهندسین متالورژی و جامعه­ی علمی ریخته­گران ایران، 1389.

7-S. Kumar, G. S. Upadhyaya, M. L. Vaidya, "Sintering of Lead Bronze Containing Tin", J. Mater. Eng, 13, PP. 237-242, 1991.

8-ش. شادپور، م. آزادبه، ع. صباحی، " بررسی تغییرات و جدایش ریزساختاری آلیاژ Cu-10Sn-10Pb تف­جوشی شده"، اولین کنفرانس تمدید و تخمین عمر سازه­های هوایی و صنعتی پیر و فرسوده، 1390.

9-M. Azadbeh, H. Danninger, C. Gierl-Mayer, " Particle Rearrangement During Liquid Phase Sintering of Cu-20Zn and Cu-10Sn-10Pb Prepared from Prealloyed Powder”, Powder Metallurgy, Vol. 56, No. 5, 2013, PP. 342-346, 2013.

10-R. M. German, "An Update on the Theory of Supersolidus Liquid Phase Sintering", Proceedings Sintering 2003, Materials Research Institute Pennsylvania State University, University Park, PA, 2003.

11-J. Liu, A. Lal, R. M. German, "Densification and Shape Retention in Supersolidus Liquid Phase Sintering", Acta Mater, Vol. 4, No. 18, PP. 4615-4626, 1999.

12-A. Lal, R. M. German, "The Role of Viscosity During Supersolidus Liquid Phase Sintering", Advances in Powder Metallurgy and Particulate Materials, PP. 169-182, 2000.

13-A. R. Upadhyaya, G. Iacocca, R. M. German, "Gravitational Effect on Compact Shaping and Microstructure during Liquid Phase Sintering", JOM, Vol. 51 (4), PP. 37-40, 1999.