Comparative study of different alloys during thermal debind-ing of powder injection molded parts

  • Authors

    • Waleed El-Garaihy Mechanical Engineering Department, Unayzah College of Engineering, Qassim University,
    • Ahmed Nassef Department of Production & Mechanical Design / Faculty of Engineering / Port-Said University
    • Medhat El-Hadek Department of Production & Mechanical Design / Faculty of Engineering / Port-Said University
    2016-10-04
    https://doi.org/10.14419/ijet.v5i4.6492
  • Capillary Flow, Powder Injection Molding, Thermal Debinding, Thermal Wicking.

  • Powder injection molding (PIM) is an interesting technique and address of research, in which a thermoplastic polymeric material is used to form the powder into the desired shape in a closed die. Binders have a crucial importance in the powder metallurgy technology as they play a vital role to provide efficient powder agglomeration and/or lubrication during shaping. At the same time, they have to be easily removed from the compacts during initial stages of sintering, using debinding process, without any damaging effect for the base material. Thermal debinding is a vital process requiring somewhat elevated temperatures to remove binder from the compact. In the current study, an investigation has been made about the effect of process variables on the debinding of injection molded pieces, by melt wicking. The debinding process was performed at temperatures ranging from 160- up to-200°C for a time duration varying from 1-up to-27 hours. All powders used in injection molding feedstock have an inherent packing porosity. Several types of alloy powders (Carbonyl iron steel, Nickel aluminide, and 316L stainless powders), with various size distributions, particle shapes, and materials are adopted to define the influence on binder incorporation resulted from this inherent porosity. Results revealed that the increase of debinding time or decrease in the wicking powder (alumina) particle size lead to an increase in the thickness of the adhered layer of alumina. When the wicking powder is very fine (0.3 mm) or has a wide particle size range (<10 mm), it becomes more dense and its debinding efficiency is decreased. At high debinding temperatures (200 °C) the rate of binder evaporation and removal increased, which leads to decreasing the cohesion of the samples yielding a shape distortion. In addition, the effect of the wicking powder (Al2O3) sizes and debinding time on the binder weight loss percentage after debinding process for FeOX, Ni3Al, and 316L has been investigated.

  • References

    1. [1] D.W. Park, D.H. Kim, H.S. Kim, Y.S. Kwon, K.K. Cho, S.G. Lim, and I..S. Ahn,†A study of the debinding and sintering behavior of T42 high-speed steel produced by powder injection molding (PIM)â€, Res Chem Intermed (40), 2014, pp 2415–2421.

      [2] M. Randall German; “Theory of Thermal Debindingâ€, The International Journal of Powder Metallurgy, Vol. 23, No. 4, 1987, pp. 237-245.

      [3] C. Wang, Z. Lu, and K. Zhang,†Evaluation of thermal debinding of injection-molded boron carbide in an ambient atmosphereâ€, Int J Adv. Manuf. Technol. (64), 2013, pp 1751–1757.

      [4] J. Rajabi, N. Muhamad, and A. Bakar Sulong,†Effect of nano-sized powders on powder injection molding: a reviewâ€, Microsyst Technol (18), 2012, pp 1941–1961.

      [5] K.S. Hwang and Y.M. Hsieh,†Comparative Study of Pore Structure Evolution During Solvent and Thermal Debinding of Powder Injection Molded Partsâ€, Metallurgical and Materials Transactions A Vol. 27A, 1996, pp 245-253. http://dx.doi.org/10.1007/BF02648403.

      [6] E. Hryha, H. Borgstrom, K. Sterky, and L. Nyborg,†Influence of the steel powder type and processing parameters on the debinding of PM compacts with gelatin binderâ€, J Therm Anal Calorim (118), 2014, pp 695–704.

      [7] D. Lin, S.T. Chung, Y. S. Kwon, and S.J. Park,†Preparation of Ti-6Al-4V feedstock for titanium powder injection moldingâ€, Journal of Mechanical Science and Technology 30 (4), 2016, pp 1859~1864. http://dx.doi.org/10.1007/s12206-016-0343-y.

      [8] H. Miura, T. Osada, and Y Itoh,†Metal Injection Molding (MIM) Processingâ€, Advances in Metallic Biomaterials, 2015, pp 27-56. http://dx.doi.org/10.1007/978-3-662-46842-5_2.

      [9] B. Hausnerova, Ivo Kuritka, and D. Bleyan,†Polyolefin Backbone Substitution in Binders for Low Temperature Powder Injection Moulding Feedstocksâ€, Molecules (19), 2014, pp 2748-2760.

      [10] Xin-lei Ni, Hai-qing Yin, L. Liu, Shan-jie Yi, and Xuan-hui Qu,†Injection molding and debinding of micro gears fabricated by micro powder injection moldingâ€, International Journal of Minerals, Metallurgy and Materials Vol. 20, No. 1, 2013, PP 82-87.

      [11] Xian-feng Yang, Jiang-hong Yang, Xie-wen Xu, Qi-cheng Liu, Zhi-peng Xie, and Wei Liu,†Injection molding of ultra-fine Si3N4 powder for gas-pressure sinteringâ€, International Journal of Minerals, Metallurgy and Materials Vol. 22, No. 6, 2015, pp 654-659. http://dx.doi.org/10.1007/s12613-015-1119-6.

      [12] A. Ruh, V. Piotter, K. Plewa, HG. Ritzhaupt-Kleiss, and J. Hauβel,â€Studies on Size Accuracy of Microgear Wheels Produced by Powder Injection Molding of Zirconia Feedstocksâ€. Int J Adv. Manuf. Technol. (58), 2012, pp 1051–1059.

      [13] A. Skalski, D. Bialo,†Accuracy of the Parts from Iron Powder Manufactured by Injection Mouldingâ€, Advances in Intelligent Systems and Computing 393, 2016, pp 261-266. http://dx.doi.org/10.1007/978-3-319-23923-1_39.

      [14] W. Diehl, H.P. Buchkremer, D. Stover; “Injection Molded Super alloy Parts Containerless HIP’edâ€, Conference Proceedings of: PM Aerospace Materials, 1987.

      [15] M. Randall; “Powder Injection Moldingâ€, German Publisher: Metal Powder Industries Federation, 1990, pp. 95-114.

      [16] R. Enneti, S.J. Park, R.M. German, and S.V. Atre,†In Situ Characterization of Strength and Distortion during Powder Metal Processingâ€, JOM, Vol. 64, No. 1, 2012, pp 28-34. http://dx.doi.org/10.1007/s11837-011-0232-x.

      [17] M. Sahli & J.-C. Gelin,†Development of a feedstock formulation based on polypropylene for micro-powder soft embossing process of 316L stainless steel micro-channel partâ€, Int J Adv. Manuf. Technol. (69), 2013, pp 2139–2148.

      [18] A. Johnsson, E. Carlstrom, L. Hermansson and R. Carlsson; “Rate-Controlled Extraction Unit for Removal of Organic Binders from Injection Molded Ceramicsâ€, Ceramic Powders, P.Vincenzini (ed.), Elsevier Scientific, Amsterdam, Nether Lands, 1983, pp. 767-772.

      [19] J. Rajabi, N. Muhamad, and A. Bakar Sulong,†Effect of nano-sized powders on powder injection molding: a reviewâ€, Microsyst Technol (18), 2012, pp 1941–1961.

      [20] 19.Zi-wei Xu, Cheng-chang Jia, Chun-jiang Kuang, and Xuan-hui Qu,†Fabrication and sintering behavior of high-nitrogen nickel-free stainless steels by metal injection moldingâ€, International Journal of Minerals, Metallurgy and Materials Vol. 17, No. 4, 2010, pp 223-228.

      [21] T.S. Wei and R.M. German, Two-stage Fast Debinding of Injection Molding Powder Compacts, US Patent, Appl. 5028367, 1991.

      [22] C.S. Aria and B.R. Patterson; “Influence of Process Variables on Debinding by Melt Wickingâ€, MPIF, APMI, 1984, Vol. 15, pp. 403-416.

      [23] R.M. German; “Prediction of Sintered Density for Bimodal Powder Mixtureâ€, Metallurgical Transactions A, Vol. 23A, May 1992, pp. 1455-1465. http://dx.doi.org/10.1007/BF02647329.

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  • How to Cite

    El-Garaihy, W., Nassef, A., & El-Hadek, M. (2016). Comparative study of different alloys during thermal debind-ing of powder injection molded parts. International Journal of Engineering & Technology, 5(4), 110-114. https://doi.org/10.14419/ijet.v5i4.6492