Hostname: page-component-7bb8b95d7b-l4ctd Total loading time: 0 Render date: 2024-10-02T16:22:26.237Z Has data issue: false hasContentIssue false

The effect of boron on the refinement of microstructure in cast cobalt alloys

Published online by Cambridge University Press:  02 March 2011

Michael J. Bermingham*
Affiliation:
Defence Material Technology Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia; and Centre for Advanced Materials Processing and Manufacturing, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia
Stuart D. McDonald
Affiliation:
Defence Material Technology Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia; and CAST Cooperative Research Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia
David H. StJohn
Affiliation:
Defence Material Technology Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia; and CAST Cooperative Research Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia; and Centre for Advanced Materials Processing and Manufacturing, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia
Matthew S. Dargusch
Affiliation:
Defence Material Technology Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia; and CAST Cooperative Research Centre, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia; and Centre for Advanced Materials Processing and Manufacturing, School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072 Australia
*
a)Address all correspondence to this author. e-mail: m.bermingham@uq.edu.au
Get access

Abstract

Controlling the grain size and morphology of cast cobalt-based components is important for optimizing a component’s in-service properties. This work investigates the role of boron on the grain size of binary cobalt–boron alloys by application of contemporary grain refinement theory. Boron solute is found to refine the width of the columnar grains but fails to promote the columnar to equiaxed transition. The lack of equiaxed grains is attributed to the thermal solidification conditions and a lack of potent nucleant particles. The refinement of the columnar grains with boron solute may be due to a growth restriction mechanism.

Type
Articles
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Beltran, A.M.: Cobalt-base alloys, in Superalloys II, edited by Sims, C.T., Stoloff, N.S., and Hagel, W.C. (Wiley, New York, 1987), p. 135.Google Scholar
2.Noble, P.C: Special materials for the replacement of human joints. Met. Forum 6, 59 (1983).Google Scholar
3.Karimpoor, A.A., Erb, U., Aust, K.T., and Palumbo, G.: High strength nanocrystalline cobalt with high tensile ductility. Scr. Mater. 49, 651 (2003).CrossRefGoogle Scholar
4.Karimpoor, A.A., Aust, K.T., and Erb, U.: Charpy impact energy of nanocrystalline and polycrystalline cobalt. Scr. Mater. 56, 201 (2007).Google Scholar
5.Karimpoor, A.A. and Erb, U.: Mechanical properties of nanocrystalline cobalt. Phys. Status Solidi A 203, 1265 (2006).Google Scholar
6.Wang, L., Gao, Y., Xu, T., and Xue, Q.: A comparative study on the tribological behavior of nanocrystalline nickel and cobalt coatings correlated with grain size and phase structure. Mater. Chem. Phys. 99, 96 (2006).Google Scholar
7.Huang, P. and Lopez, H.F.: Strain induced ε-martensite in a Co-Cr-Mo alloy: Grain size effects. Mater. Lett. 39, 244 (1999).CrossRefGoogle Scholar
8.Della Valle, A.G., Becksac, B., Anderson, J., Wright, T., Nestor, B., Pellicci, P.M., and Salvati, E.A.: Late fatigue fracture of a modern cemented forged cobalt chrome stem for total hip arthroplasty—A report of 10 cases. J. Arthroplasty 20, 1084 (2005).CrossRefGoogle Scholar
9.Huang, P. and Lopez, H.F.: Athermal ε-martensite in a Co-Cr-Mo alloy: Grain size effects. Mater. Lett. 39, 249 (1999).CrossRefGoogle Scholar
10.Freeman, W.R.: Investment casting, in Superalloys II, edited by Sims, C.T., Stoloff, N.S., and Hagel, W.C. (Wiley, New York, 1987), p. 411.Google Scholar
11.Reed, R.C.: The Superalloys Fundamentals and Applications (Cambridge University Press, New York, 2006), p. 372.Google Scholar
12.Xiaoping, M., Yingju, L., and Yuansheng, Y.: Grain refinement effect of a pulsed magnetic field on as-cast superalloy K417. J. Mater. Res. 24, 2670 (2009).Google Scholar
13.Watmough, T.: Mold treatment to grain refine investment cast cobalt-chromium alloys. Trans. Am. Foundrymen’s Soc. 8, 481 (1980).Google Scholar
14.Jin, W., Bai, F., Li, T., and Yin, G.: Grain refinement of superalloy IN100 under the action of rotary magnetic fields and inoculants. Mater. Lett. 62, 1585 (2008).Google Scholar
15.Liu, F., Guo, X.F., and Yang, G.C.: Structural stability and non-catalytic nucleation inhibition effect of Si-Zr-B mold coating on superalloy melt. Mater. Sci. Technol. 17, 1102 (2001).Google Scholar
16.Liu, F. and Yang, G.C.: Rapid solidification of highly undercooled bulk liquid superalloy: Recent developments, future directions. Int. Mater. Rev. 51, 145 (2006).CrossRefGoogle Scholar
17.StJohn, D.H., Qian, M.A., Easton, M.A., Cao, P., and Hildebrand, Z.: Grain refinement of magnesium alloys. Metall. Mater. Trans. A 36, 1669 (2005).Google Scholar
18.Easton, M.A. and StJohn, D.H.: An analysis of the relationship between grain size, solute content, and the potency and number density of nucleant particles. Metall. Mater. Trans. A 36, 1911 (2005).CrossRefGoogle Scholar
19.Bermingham, M.J., McDonald, S.D., StJohn, D.H. and Dargusch, M.S.: Latest developments in understanding grain refinement of cast titanium. Mater. Sci. Forum 618619, 315 (2009).Google Scholar
20.Greer, A.L., Bunn, A.M., Tronche, A., Evans, P.V., and Bristow, D.J.: Modelling of inoculation of metallic melts: Application to grain refinement of aluminium by Al-Ti-B. Acta Mater. 48, 2823 (2000).Google Scholar
21.Dargusch, M.S., Bermingham, M.J., McDonald, S.D., and StJohn, D.H.: Effects of boron on microstructure in cast zirconium alloys. J. Mater. Res. 25, 1695 (2010).CrossRefGoogle Scholar
22.Maxwell, I. and Hellawell, A.: A simple model for grain refinement during solidification. Acta Mater. 23, 229 (1975).Google Scholar
23.Easton, M.A. and StJohn, D.H.: Grain refinement of aluminium alloys: Part II. Confirmation of, and a mechanism for, the solute paradigm. Metall. Mater. Trans. A 30A, 1625 (1999).Google Scholar
24.Alloy phase diagrams, in ASM Handbook, Vol. 3 (ASM International, Materials Park, OH, 1990).Google Scholar
25.Greer, A.L., Cooper, P.S., Meredith, M.W., Schnider, W., Schumacher, P., Spittle, J.A., and Tronche, A.: Grain refinement of aluminium alloys by inoculation. Adv. Eng. Mater. 5, 81 (2003).CrossRefGoogle Scholar
26.Bermingham, M.J., McDonald, S.D., StJohn, D.H., and Dargusch, M.S.: Beryllium as a grain refiner in titanium. J. Alloy. Comp. 481, L20 (2009).CrossRefGoogle Scholar
27.Hunt, J.D.: Steady state columnar and equiaxed growth of dendrites and eutectic. Mater. Sci. Eng. 65, 75 (1984).CrossRefGoogle Scholar
28.Drewes, K., Schaefers, K., Rosner-Kuhn, M., and Frohberg, M.G.: Measurements of dendritic growth and recalescence rates in undercooled melts of cobalt. Mater. Sci. Eng. A 241, 99 (1997).CrossRefGoogle Scholar
29.Genders, R.: The interpretation of the macrostructure of cast metals. J. Inst. Met. 35, 259 (1926).Google Scholar
30.Charlmers, B.: Structure of ingots. J. Aust. Inst. Met. 8, 255 (1963).Google Scholar
31.Jackson, K.A., Hunt, J.D., Uhlmann, D.R., and Seward, T.P. III: On origin of equiaxed zone in castings. Trans. Metall. Soc. AIME 236, 149 (1966).Google Scholar
32.Ohno, A., Motegi, T., and Soda, H.: Origin of the equiaxed crystals in castings. Trans. Iron Steel Inst. Jpn. 11, 18 (1971).Google Scholar
33.Hutt, J. and StJohn, D.H.: The origins of the equiaxed zone—Review of theoretical and experimental work. Int. J. Cast Met. Res. 11, 13 (1998).CrossRefGoogle Scholar
34.Zhuang, L.Z. and Langer, E.W.: Effects of cooling rate control during the solidification process on the microstructure and mechanical properties of cast Co-Cr-Mo alloy used for surgical implants. J. Mater. Sci. 24, 381 (1989).Google Scholar
35.Riddihough, M.: Properties of cobalt-base investment-cast alloys. Foundry Trade J. 5, 421 (1959).Google Scholar
36.Gomez, M., Mancha, H., Salinas, A., Rodriguez, J.L., Escobedo, J., Castro, M., and Mendez, M.: Relationship between microstructure and ductility of investment cast ASTM F-75 implant alloy. J. Biomed. Mater. Res. 34, 157 (1997).3.0.CO;2-P>CrossRefGoogle ScholarPubMed