Preparation of Fiber-Reinforced Shell by Airflow Placement Fiber Technology for Investment Casting

  • Yanfen Li
  • Xiangdong LiuEmail author
  • Kai LűEmail author
  • Xiaodong Du


A new process for preparing fiber-reinforced silica sol shells for investment casting is proposed. The influence of fiber length on bending strength of shell is studied under the condition that fibers are not agglomerated or clustered. Polypropylene fibers were suspended under the action of air currents and adhered to the surface of shell with back-up slurry in the fiber placement device. Three millimeter and six millimeter lengths of fiber were used as reinforcing agents for the investment shell. The results showed that fibers could be placed uniformly on the surface of shell with slurry by air flowing in the fiber placement device, thereby enhancing the strength of the fiber-reinforced shell. Green bending strength of shell with additive of 6-mm-length fiber was higher than that of 3-mm-length fiber. This was due to the fact that the fibers were scattered into a reticular formation and the action of bridge connection between the longer fiber and matrix was stronger. Compared with the fiber of 3 mm length, the scanning electron microscope morphology of 6-mm-length fiber had typical characteristics on the fracture section of shell, which meant that fiber was pulled out from the shell with large mechanical force.


fiber-reinforced shell placement fiber investment casting bending strength characteristics of fracture section 



This project is supported by National Natural Science Foundation of China (Grant No. 51865042); National Natural Science Foundation of Inner Mongolia (Grant No. 2018MS05051); Science Foundation for Universities in Inner Mongolia Autonomous Region of China (Grant No. NJZZ17080); and Inner Mongolia University of technology Foundation (Grant No. X201412).


  1. 1.
    S. Pattnaik, D.B. Karunakar, P.K. Jha, Developments in investment casting process—a review. J. Mater. Process. Technol. 212, 2332 (2012)CrossRefGoogle Scholar
  2. 2.
    D. Zhang, Y. Cheng, R. Jiang, Turbine Blade Investment Casting. Die Technology, vol. 8 (National Defense Industry Press, Beijing, 2018)CrossRefGoogle Scholar
  3. 3.
    S. Jones, C. Yuan, Advances in shell moulding for investment casting. J. Mater. Process. Technol. 135, 258 (2003)CrossRefGoogle Scholar
  4. 4.
    W. Everhart, S. Lekakh, V. Richards, J. Chen et al., Corner strength of investment casting shells. Int. J. Metalcasting 7, 21 (2013)CrossRefGoogle Scholar
  5. 5.
    C. Yuan, S. Jones, Investigation of fiber modified ceramic molds for investment casting. J. Eur. Ceram. Soc. 23, 329 (2003)CrossRefGoogle Scholar
  6. 6.
    S. Jones, C. Yuan, Organic fibre modified ceramic shell moulding for investment casting. Mater. Sci. Technol. 18, 1565 (2002)CrossRefGoogle Scholar
  7. 7.
    F. Wang, F. Li, B. He, B. Sun, Microstructure and strength of needle coke modified ceramic casting molds. Ceram. Int. 40, 479–486 (2014)CrossRefGoogle Scholar
  8. 8.
    S. Kumar, D.B. Karunakar, Enhancing the permeability and properties of ceramic shell in investment casting process using ABS powder and needle coke. Int. J. Metalcasting (2019). Google Scholar
  9. 9.
    K. Lü, X. Liu, Z. Du, Y. Li, Bending strength and fracture surface topography of natural fiber-reinforced shell for investment casting process. China Foundry 13, 211 (2016)CrossRefGoogle Scholar
  10. 10.
    K. Lü, X. Liu, Y. Lu, Z. Du, The interfacial characteristics and action mechanism of fibre-reinforced shell for investment casting. Int. J. Manuf. Technol. 93, 2895 (2017)CrossRefGoogle Scholar
  11. 11.
    G. Lu, C. Ji, Q. Yan, Effects and enhanced behavior of ceramic fiber length on bending strength and breathability of composite shell for investment casting. Acta Materiae Compositae Sinica 34, 865 (2017)Google Scholar
  12. 12.
    R. Van hout, L. Sabban, A. Chen, The use of high-speed PIV and holographic cinematography in the study of fiber suspension flows. Acta Mech. 224, 2263 (2013)CrossRefGoogle Scholar
  13. 13.
    X. Wang, Y. Xiao, Research of the gas-solid flow character based on the DEM method. J. Therm. Sci. 20, 521 (2011)CrossRefGoogle Scholar
  14. 14.
    H. Xu, C.K. Aidun, Characteristics of fiber suspension flow in a rectangular channel. Int. J. Multiph. Flow 31, 318 (2005)CrossRefGoogle Scholar
  15. 15.
    C.M. Hrenya, J.L. Sinclair, Effects of particle-phase turbulence in gas–solid flows. Aiche J. 43, 853 (1997)CrossRefGoogle Scholar
  16. 16.
    Y. Yamamoto, M. Potthoff, T. Tanaka, T. Kajishima, Y. Tsuji, Large-eddy simulation of turbulent gas-particle flow in a vertical channel effect of considering inter-particle collisions. J. Fluid Mech. 442, 303 (2001)CrossRefGoogle Scholar
  17. 17.
    Y. Diao, X. Li, P. Gu, H. Li, Numerical simulation of gas–solid flow in the axisymmetric inlets square separator. Korean J. Chem. Eng. 26, 879 (2009)CrossRefGoogle Scholar

Copyright information

© American Foundry Society 2019

Authors and Affiliations

  1. 1.School of Materials Science and EngineeringInner Mongolia University of TechnologyHohhotChina
  2. 2.Key Laboratory of Materials Processing and Control Engineering of Inner Mongolia Autonomous RegionHohhotChina

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