Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-28T11:37:58.817Z Has data issue: false hasContentIssue false

In situ electrochemical nanoindentation of FeAl (100) single crystal: Hydrogen effect on dislocation nucleation

Published online by Cambridge University Press:  31 January 2011

Afrooz Barnoush*
Affiliation:
Saarland University, Department of Materials and Methods, Saarbruecken 66123, Germany
Christian Bies
Affiliation:
Saarland University, Department of Materials and Methods, Saarbruecken 66123, Germany
Horst Vehoff
Affiliation:
Saarland University, Department of Materials and Methods, Saarbruecken 66123, Germany
*
a) Address all correspondence to this author.e-mail: [email protected]
Get access

Abstract

The hydrogen effect on dislocation nucleation in FeAl single crystal with (100) surface orientation has been examined with the aid of a specifically designed nanoindentation setup for in situ electrochemical experiments. The effect of the electrochemical potential on the indent load–displacement curve, especially the unstable elastic-plastic transition (pop-in), was studied in detail. The observations showed a reduction in the pop-in load for both samples due to in situ hydrogen charging, which is reproducibly observed within sequential hydrogen charging and discharging. Clear evidence is provided that hydrogen atoms facilitate homogeneous dislocation nucleation.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

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.Stoloff, N.S. and Liu, C.T.: Environmental embrittlement of iron aluminides. Intermetallics 2, 75 (1994).CrossRefGoogle Scholar
2.Cohron, J.W., Lin, Y., Zee, R.H., and George, E.P.: Room-temperature mechanical behavior of FeAl: Effects of stoichiometry, environment, and boron addition. Acta Mater. 46, 6245 (1998).CrossRefGoogle Scholar
3.Baker, I., Wu, D., Kruijver, S.O., and George, E.P.: The effects of environment on the room-temperature mechanical behavior of single-slip oriented FeAl single crystals. Mater. Sci. Eng., A 329, 729 (2002).CrossRefGoogle Scholar
4.Liu, C.T., George, E.P., Maziasz, P.J., and Schneibel, J.H.: Recent advances in B2 iron aluminide alloys: Deformation, fracture and alloy design. Mater. Sci. Eng., A 258, 84 (1998).CrossRefGoogle Scholar
5.Wittmann, M., Wu, D., Baker, I., George, E.P., and Heatherly, L.: The role of edge and screw dislocations on hydrogen embrittlement of Fe–40Al. Mater. Sci. Eng., A 319, 352 (2001).CrossRefGoogle Scholar
6.Borchers, C., Michler, T., and Pundt, A.: Effect of hydrogen on the mechanical properties of stainless steels. Adv. Eng. Mater. 10, 11 (2008).Google Scholar
7.Pundt, A. and Kirchheim, R.: Hydrogen in metals: Microstructural aspects. Annu. Rev. Mater. Res. 36, 555 (2006).CrossRefGoogle Scholar
8.Olden, V., Thaulow, C., Johnsen, R., Ostby, E., and Berstad, T.: Application of hydrogen influenced cohesive laws in the prediction of hydrogen induced stress cracking in 25%Cr duplex stainless steel. Eng. Fract. Mech. 75, 2333 (2008).CrossRefGoogle Scholar
9.Chateau, J.P., Delafosse, D., and Magnin, T.: Numerical simulations of hydrogen-dislocation interactions in fcc stainless steels. Part 1: Hydrogen-dislocation interactions in bulk crystals. Acta Mater. 50, 1507 (2002).CrossRefGoogle Scholar
10.Vehoff, H. and Klameth, H.K.: Hydrogen embrittlement and trapping at crack tips in Ni-single crystals. Acta Metall. 33, 955 (1985).CrossRefGoogle Scholar
11.Vehoff, H., Laird, C., and Duquette, D.J.: The effects of hydrogen and segregation on fatigue crack nucleation at defined grain-boundaries in nickel bicrystals. Acta Metall. 35, 2877 (1987).CrossRefGoogle Scholar
12.Kirchheim, R.: Reducing grain boundary, dislocation line and vacancy formation energies by solute segregation. I.I. Experimental evidence and consequences. Acta Mater. 55, 5139 (2007).Google Scholar
13.Kirchheim, R.: Interaction of hydrogen with dislocations in palladium. 2. Interpretation of activity results by a Fermi-Dirac distribution. Acta Metall. 29, 845 (1981).CrossRefGoogle Scholar
14.Ferreira, P.J., Robertson, I.M., and Birnbaum, H.K.: Hydrogen effects on the interaction between dislocations. Acta Mater. 46, 1749 (1998).CrossRefGoogle Scholar
15.Bond, G.M., Robertson, I.M., and Birnbaum, H.K.: On the determination of the hydrogen fugacity in an environmental cell TEM facility. Scr. Metall. 20, 653 (1986).CrossRefGoogle Scholar
16.Robertson, I.M. and Teter, D.: Controlled environment transmission electron microscopy. Microsc. Res. Tech. 42, 260 (1998).3.0.CO;2-U>CrossRefGoogle ScholarPubMed
17.Katz, Y., Tymiak, N., and Gerberich, W.W.: Nanomechanical probes as new approaches to hydrogen/deformation interaction studies. Eng. Fract. Mech. 68, 619 (2001).CrossRefGoogle Scholar
18.Henning, M. and Vehoff, H.: Local mechanical behavior and slip band formation within grains of thin sheets. Acta Mater. 53, 1285 (2005).CrossRefGoogle Scholar
19.Welsch, M.T., Henning, M., Marx, M., and Vehoff, H.: Measuring the plastic zone size by orientation gradient mapping (OGM) and electron channeling contrast imaging (ECCI). Adv. Eng. Mater. 9, 31 (2007).CrossRefGoogle Scholar
20.Yang, B. and Vehoff, H.: Dependence of nanohardness upon indentation size and grain size—A local examination of the interaction between dislocations and grain boundaries. Acta Mater. 55, 849 (2007).CrossRefGoogle Scholar
21.Durst, K., Franke, O., Bohner, A., and Goken, M.: Indentation size effect in Ni–Fe solid solutions. Acta Mater. 55, 6825 (2007).CrossRefGoogle Scholar
22.Barnoush, A. and Vehoff, H.: In situ electrochemical nanoindenta-tion of a nickel (111) single crystal: Hydrogen effect on pop-in behaviour. Int. J. Mater. Res. 97, 1224 (2006).CrossRefGoogle Scholar
23.Nibur, K.A., Bahr, D.F., and Somerday, B.P.: Hydrogen effects on dislocation activity in austenitic stainless steel. Acta Mater. 54, 2677 (2006).CrossRefGoogle Scholar
24.Durst, K., Backes, B., Franke, O., and Goken, M.: Indentation size effect in metallic materials: Modeling strength from pop-in to macroscopic hardness using geometrically necessary dislocations. Acta Mater. 54, 2547 (2006).Google Scholar
25.Borchers, C., Laudahn, U., Pundt, A., Fahler, S., Krebs, H.U., and R Kirchheim: Influence of hydrogen loading on the microstructure of niobium-palladium multilayers. Philos. Mag. A 80, 543 (2000).CrossRefGoogle Scholar
26.Cizek, J., Prochazka, T., Danis, S., Cieslar, M., Brauer, G., Anwand, W., Kirchheim, R., and Pundt, A.: Hydrogen-induced defects in niobium. J. Alloys Compd. 446, 479 (2007).CrossRefGoogle Scholar
27.Pundt, A., Northemann, K., and Schmidt, S.: Hydrogen-related surface modifications of 20 nm thin straight-sided niobium nano-wires and niobium meander-films. J. Alloys Compd. 446, 549 (2007).CrossRefGoogle Scholar
28.Barnoush, A. and Vehoff, H.: Electrochemical nanoindentation: A new approach to probe hydrogen/deformation interaction. Scr. Mater. 55, 195 (2006).CrossRefGoogle Scholar
29.Barnoush, A. and Vehoff, H.: In situ electrochemical nanoindentation: A technique for local examination of hydrogen embrittlement. Corros. Sci. 50, 259 (2008).CrossRefGoogle Scholar
30.Barnoush, A. and Vehoff, H.: Hydrogen embrittlement of aluminum in aqueous environments examined by in situ electrochemical nanoindentation. Scr. Mater. 58, 747 (2008).CrossRefGoogle Scholar
31.Frangini, S., Giorgi, R., Lascovich, J., and Mignone, A.: XPS study of passive films formed on an iron-aluminum intermetallic compound in acid-solution. Surf. Interface Anal. 21, 435 (1994).CrossRefGoogle Scholar
32.Gerberich, W.W., Venkataraman, S.K., Huang, H., Harvey, S.E., and Kohlstedt, D.L.: The injection of plasticity by millinewton contacts. Acta Metall Mater. 43, 1569 (1995).CrossRefGoogle Scholar
33.Chiu, Y.L. and Ngan, A.H.W.: Time-dependent characteristics of incipient plasticity in nanoindentation of a Ni3Al single crystal. Acta Mater. 50, 1599 (2002).CrossRefGoogle Scholar
34.Schuh, C.A. and Lund, A.C.: Application of nucleation theory to the rate dependence of incipient plasticity during nanoindentation. J. Mater. Res. 19, 2152 (2004).CrossRefGoogle Scholar
35.Bei, H., George, E.P., Hay, J.L., and Pharr, G.M.: Influence of indenter tip geometry on elastic deformation during nanoindentation. Phys. Rev. Lett. 95, 1 (2005).CrossRefGoogle ScholarPubMed
36.Lilleodden, E.T., Zimmerman, J.A., Foiles, S.M., and Nix, W.D.: Atomistic simulations of elastic deformation and dislocation nucleation during nanoindentation. J. Mech. Phys. Solids 51, 901 (2003).Google Scholar
37.Minor, A.M., Lilleodden, E.T., Stach, E.A., and Morris, J.W.: Direct observations of incipient plasticity during nanoindentation of Al. J. Mater. Res. 19, 176 (2004).Google Scholar
38.Harmouche, M.R. and A Wolfenden: Temperature and composition dependence of Young modulus for ordered-B2 polycrystalline-CoAl and polycrystalline-FeAl. Mater. Sci. Eng. 84, 35 (1986).CrossRefGoogle Scholar
39.Vailhe, C. and Farkas, D.: Shear faults and dislocation core structure simulations in B2 FeAl. Acta Mater. 45, 4463 (1997).CrossRefGoogle Scholar
40.Hirth, J.P. and Lothe, J.: Theory of Dislocations (McGraw-Hill Book Co., New York, 1968).Google Scholar
41.Kittel, C.: Introduction to Solid State Physics, 4th ed. (John Wiley, New York, 1971).Google Scholar
42.Guinea, F., Rose, J.H., Smith, J.R., and Ferrante, J.: Scaling relations in the equation of state, thermal-expansion, and melting of metals. Appl. Phys. Lett. 44, 53 (1984).CrossRefGoogle Scholar
43.Rose, J.H., Smith, J.R., Guinea, F., and Ferrante, J.: Universal features of the equation of state of metals. Phys. Rev. B 29, 2963 (1984).CrossRefGoogle Scholar
44.Barnoush, A.: Hydrogen embrittlement, revisited by in situ electrochemical nanoindentation. Ph.D. Thesis, Saarland University, Saarbrücken, Germany, 2008, p. 257.Google Scholar