بررسی تغییرات ایجاد شده در حین تف‌جوشی فاز مایع آلیاژهای حاوی اجزاء تبخیر شونده

نویسندگان

1 1- دانشکده مهندسی مواد، دانشگاه صنعتی سهند تبریز

2 2- باشگاه پژوهشگران جوان و نخبگان، دانشگاه آزاد اسلامی، واحد اهر

چکیده

هدف از انجام این پژوهش بررسی امکان بروز پدیده پاشنه فیلی در آلیاژهای تف‌جوشی شده حاوی عامل تبخیر شونده است. به این منظور قطعات برنجی با ترکیب Cu-28Zn در محدوده دمایی 890-970 درجه ‌سانتی‌گراد به‌مدت 20 دقیقه تف‌جوشی شدند. از قطعات برنجی در شرایط مختلف تف‌جوشی به­صورت درجا، عکس­برداری شد. نتیجه این­ بود که با وجود کشیده شدن مذاب به سمت نواحی پایین بر اثر نیروی جاذبه زمین، پدیده پاشنه فیلی در این قطعات مشاهده نشد و به جای آن قطعات دچار تورم شدند. تغییر ترکیب شیمیایی و افزایش اندازه حفرات در اثر تبخیر روی را می­توان به عنوان اصلی­ترین عامل بروز این پدیده دانست.

کلیدواژه‌ها


عنوان مقاله [English]

An Investigation of Evolutions during Liquid Phase Sintering of Systems with Volatile Components

نویسندگان [English]

  • M. Mousapour 1
  • M. Azadbeh 1
  • A. Mohammadzadeh 2
1 1- Department of Materials Engineering, Sahand University of Technology, Tabriz
2 2- Young Researchers and Elite Club, Ahar Branch, Islamic Azad University, Ahar
چکیده [English]

In this paper, the possibility of elephant foot phenomenon in sintered alloys with volatile components has been studied. To do this, Cu-28Zn brass samples were sintered at the range of 890-970°C for 20 min. The in situ images from brass samples were taken at various sintering conditions. It is concluded that although liquid is pulled down by gravity, but elephant phenomenon was not appeared in these compacts. Instead, the samples were swelled. Chemical composition change and pores coarsening due to zinc evaporation could be considered as the main cause of swelling in brass compacts.

کلیدواژه‌ها [English]

  • Supersolidus sintering
  • Elephant foot phenomenon
  • Zinc evaporation
  • Swelling
  • Microstructural gradient
1. German, R.M., "Supersolidus Liquid Phase Sintering of Prealloyed Powders", Metallurgical and Materials Transactions A, Vol. 28, pp. 1553-1567, 1997.
2. Liu, Y., Tandon, R. and German, R.M., "Modeling of Supersolidus Liquid Phase Sintering, Part. I: Capillary Force", Metallurgical and Materials Transactions A, Vol. 26 (A), pp. 2415-2422, 1995.
3. Lal, A. and German, R.M., "The Role of Viscosity during Supersolidus Liquid Phase Sintering", Advances in Powder Metallurgy and Particulate Materials, pp. 169-182, 2000.
4. German, R.M., "An Update on the Theory of Supersolidus Liquid Phase Sintering", Proceedings Sintering, Materials Research Institute Pennsylvania State University, University Park, PA, 2003.
5. Liu, J., Lal, A. and German, R.M., "Densification and Shape Retention in Supersolidus Liquid Phase Sintering", Acta Material, Vol. 4, No. 18, pp. 4615-4626, 1999.
6. Upadhyaya, A., Iacocca, R.G. and German, R.M., "Gravitational Effect on Compact Shaping and Microstructure during Liquid Phase Sintering", Journal of Materials, Vol. 51, No. 4, pp. 37-40, 1999.
7. Bollina, R., "In situ Evaluation of Supersolidus Liquid Phase Sintering Phenomena of Stainless Steel 316L: Densification and Distortion", Ph.D. Thesis, The Pennsylvania State University, University Park, PA, 2005.
8. Wu, Y., German, R.M., Marx, B., Bollina, R. and Bell, M., "Characteristics of Densification and Distortion of Ni-Cu Liquid Phase Sintered Tungsten Heavy Alloy", Materials science and engineering A, 344, pp. 158-167, 2003.
9. Terletskii, V.E., "Investigation of Conditions of Production of Brass Powders and of the Sintering of Parts from them", Author's Abstract of Candidate's Dissertation, Kiev, 1972.
10. Palmer, E. and Grimme, D., "Investigation of the Possibility of Production of P/M Brass Parts, New Materials Produced by Powder Metallurgy Methods [Russian Translation]", Metallurgy, Moscow,
pp. 137-146, 1966.
13. Dovydenkova, I.V. and Radomyselskii, I.D., "Production and Properties of Constructional Parts from Copper and Copper Alloy Powders: A Review", Poroshk. Metallurgy, Vol. 255, No. 3, pp. 56-64, 1984.
14. Marchi, C.S., Felberbaum, L. and Mortensen, A., "The Effect of Gravity on Solution Reprecipitation during Liquid Phase Sintering". Metallurgical and Materials Transactions A, Vol. 31, No. 397, 2000.
15. Mohammadzadeh, A., Azadbeh, M. and Namini, A., "Densification and Volumetric Change during Supersolidus Liquid Phase Sintering of Prealloyed Brass Cu28Zn Powder: Modeling and Optimization", Science of Sintering, Vol. 46, pp. 23-35, 2014.
16. Sabahi Namin, A., Azadbeh, M. and Mohammadzadeh, A., "Microstructure and Densification Behavior of Liquid Phase Sintered Cu-28Zn Prealloyed Powder", Science of Sintering, Vol. 45, pp. 351-362, 2013.
17. Azadbeh, M., Danninger, H., Mohammadzadeh, A. and Gierl-Mayer, C., "Effect of Green Density on Fragmentation-Rearrangement in Supersolidus Liquid Phase Sintering of Prealloyed Brass Powder", Euro PM, Manuscript Refereed by Professor Jan Kazior, 2014.
19. Mohammadzadeh A, Azadbeh M, Danninger H., “New concept in analysis of supersolidus liquid phase sintering of alpha brass”, Powder Metallurgy, Vol. 58, pp. 123-132, 2015.
20. Azadbeh, M., Danninger, H. and Gierl-Mayer, C., "Macroscopic Illustration of Zn Evaporation during Liquid Phase Sintering of Cu-28Zn Prepared from Prealloyed Powder", Sintering, Atmosphere and Atmosphere Control, Euro PM, Manuscript Refereed by Professor Francisco Castro, 2013.

تحت نظارت وف ایرانی