Skip to main content
Log in

The Effects of Surface Roughness and Metal Temperature on the Heat-Transfer Coefficient at the Metal Mold Interface

  • Published:
Metallurgical and Materials Transactions B Aims and scope Submit manuscript

Abstract

This article focused on the effects of surface roughness and temperature on the heat-transfer coefficient at the metal mold interface. The experimental work was carried out in a unique and versatile apparatus, which was instrumented with two types of sensors, thermocouples, and linear variable differential transformers (LVDTs). The monitoring of the two types of sensors was carried out simultaneously during solidification. The concurrent use of two independent sensors provided mutually supportive data, thereby strengthening the validity of the interpretations that were made. With this type of instrumentation, it was possible to measure temperature profiles in mold and casting, as well as the air gap at the metal mold interface. Commercial purity aluminum was cast against steel and high carbon iron molds. Each type of mold had a unique surface roughness value. Inverse heat-transfer analysis was used to estimate the heat-transfer coefficient and the heat flux at the metal mold interface. A significant drop in the heat-transfer coefficient was registered, which coincided with the time period of the air gap formation, detected by the LVDT. An equation of the form \(h\, = \,\frac{1} {{b^{\ast}A + c}}\, + \,d\) was found to provide excellent correlation between the heat-transfer coefficient and air gap size. In general, an increase in mold surface roughness results in a decrease in the heat-transfer coefficient at the metal mold interface. On the other hand, a rise in liquid metal temperature results in a higher heat-transfer coefficient.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15

Similar content being viewed by others

Abbreviations

A :

air gap size (mm)

b :

equation constant

c :

equation constant

d :

equation constant

C P :

specific heat

F :

sum-of-squares function

h :

heat-transfer coefficient (W/m2 K)

k :

thermal conductivity (W/m K)

I :

upper limit for F

l :

iteration step

n :

number of temperature measurement

m :

time-step number for heat flux

\( \bar{q} \) :

vector elements of heat flux at the interface corresponding to various temperature measurements (W/m2)

R a :

specific surface roughness

T :

calculated temperature

T cs :

casting surface temperature

T ms :

mold surface temperature

Th :

thermocouple identification symbol

X :

coordinate

Y :

measured temperature

ε 1 :

epsilon, incremental value

ε 2 :

epsilon, acceptance criterion

ε cs :

emissivity of the casting

ε ms :

emissivity of the metal mold

α :

thermal diffusivity

δ :

heat flux increment

ρ :

density (kg/m3)

σ :

Stefan–Boltzman constant

REFERENCES

  1. T.S. Prasanna Kumar, K. Narayan Prabhu: Metall. Trans. B, 1991, vol. 22B, pp. 717–29

    Google Scholar 

  2. W.D. Griffiths: Metall. Mater. Trans. B, 1999, vol. 30B, pp. 473–82

    Article  Google Scholar 

  3. L.J.D. Sully: AFS Trans., 1976, vol. 84, pp. 735–44

    Google Scholar 

  4. M. Trovant, S. Argyropoulos: Metall. Mater. Trans. B, 2000, vol. 31B, pp. 75–86

    Article  Google Scholar 

  5. M. Trovant, S. Argyropoulos: Metall. Mater. Trans. B, 2000, vol. 31B, pp. 87–96

    Article  Google Scholar 

  6. Y. Nishida, W. Droste, S. Engler: Metall. Trans. B, 1986, vol. 17B, pp. 833–44

    Google Scholar 

  7. D.G.R. Sharma, M. Krishnan: AFS Trans., 1991, vol. 99, pp. 429–38

    Google Scholar 

  8. C.A. Muojekwu, I.V. Samarasekera, J.K. Brimacombe: Metall. Mater. Trans. B, 1995, vol. 26B, pp. 361–82

    Google Scholar 

  9. K. Ho, R.D. Pehlke: Metall. Trans. B, 1985, vol. 16B, pp. 585–94

    Google Scholar 

  10. K. Ho, R.D. Pehlke: AFS Trans., 1984, vol. 92, pp. 587–98

    Google Scholar 

  11. R.D. Pehlke: Proc. Modelling of Casting, Welding and Advanced Solidification Processes VII, M. Cross and J. Campbell, eds., TMS, Warrendale, PA, 1995, pp. 373–80

  12. P. Schmidt, I.L. Svensson: Proc. 7th Int. Conf. Numerical Methods in Thermal Problems, Pineridge Press Ltd., Swansea, United Kingdom, 1991, vol. VII. I, pp. 236–47

    Google Scholar 

  13. P. Schmidt: Mater. Sci. Eng. A, 1993, vol. A173, pp. 271–74

    Google Scholar 

  14. T.S. Prasanna Kumar, K. Narayan Prabhu: Metall. Trans. B, 1991, vol. 22B, pp. 717–29

    Google Scholar 

  15. J. Isaac, G.P. Reddy, G.K. Sharma: Br. Foundryman, 1985, vol. 78, pp. 465–68

    Google Scholar 

  16. M. Krishnan, D.G.R. Sharma: AFS Trans., 1994, vol. 102. pp. 769–74

    Google Scholar 

  17. A.-W.M. Assar: J. Mater. Sci. Lett., 1992, vol. 11, pp. 601–06

    Article  Google Scholar 

  18. M.A. Taha, N.A. El-Mahallawy, A.-W.M. Assar, R.M. Hammouda: J. Mater. Sci., 1992, vol. 27, pp. 3467–73

    Article  Google Scholar 

  19. M. Krishnan, D.G.R. Sharma: Scripta Metall. Mater., 1993, vol. 28, pp. 447–51

    Article  Google Scholar 

  20. M. Bamberger, B.Z. Weiss, M.M. Stupel: Mater. Sci. Technol., 1987, vol. 3, pp. 49–56

    Google Scholar 

  21. E. Gozlan and M. Bamberger: Z. Metallkd., 1987, pp. 677–82

  22. N.A. El-Mahallawy and A.M. Assar: J. Mater. Sci., 1991, vol. 26, pp. 1729–33

  23. F. Chiesa: AFS Trans., 1990, vol. 98, pp. 193–200

    Google Scholar 

  24. A.M. Assar: Mater. Sci. Technol., 1977, vol. 13, pp. 702–04

    Google Scholar 

  25. M. Prates, H. Biloni: Metall. Trans. A, 1972, vol. 3, pp. 1501–10

    Google Scholar 

  26. B.L. Coates, S.A. Argyropoulos, and B. Melissari: Proc. Int. Symp. on Enabling Technologies for Light Metals and Composite Materials and Their End-Products, TMS-CIM, 2002, pp. 487–501

  27. T. Loulou, E.A. Artyukhin, J.P. Bardon: Int. J. Heat Mass Transfer, 1999, vol. 42, pp. 2119–27

    Article  Google Scholar 

  28. T. Loulou, E.A. Artyukhin, J.P. Bardon: Int. J. Heat Mass Transfer, 1999, vol. 42, pp. 2129–42

    Article  Google Scholar 

  29. G.X. Wang, E.F. Matthys: Int. J. Heat Mass Transfer, 2002, vol. 45, pp. 4967–81

    Article  Google Scholar 

  30. W. Wang, H.H. Qiu: Int. J. Heat Mass Transfer, 2002, vol. 45, pp. 2043–53

    Article  MathSciNet  Google Scholar 

  31. A. Venkatesan, K. Suchithra, and A. Rajadurai: AFS Trans., 2005, vol. 113, in CD format, paper 05-069(02).pdf

  32. R. Kayikci, W.D. Griffiths, C. Strangeways: J. Mater. Sci., 2003, vol. 38, pp. 3683–87

    Article  Google Scholar 

  33. J.V. Beck: Int. J. Heat Mass Transfer, 1970, vol. 13, pp. 703–16

    Article  Google Scholar 

  34. SeropeKalpakjian, Steven R. Schmid: Manufacturing Engineering and Technology, Prentice Hall, Elmsford, NJ, 2000, 4th ed., p. 272.

    Google Scholar 

  35. F.P. Incropera and D.P. Dewitt: Fundamentals of Heat and Mass Transfer, 3rd ed., John Wiley & Sons, New York, NY, 1990, Appendix A, p. A15

Download references

ACKNOWLEDGMENT

The authors are indebted to the Natural Sciences and Engineering Research Council of Canada for its financial support.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to STAVROS A. ARGYROPOULOS.

Additional information

Manuscript submitted July 1, 2005.

Rights and permissions

Reprints and permissions

About this article

Cite this article

COATES, B., ARGYROPOULOS, S.A. The Effects of Surface Roughness and Metal Temperature on the Heat-Transfer Coefficient at the Metal Mold Interface. Metall Mater Trans B 38, 243–255 (2007). https://doi.org/10.1007/s11663-007-9020-y

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11663-007-9020-y

Keywords

Navigation