Skip to main content
Log in

Electron backscatter diffraction investigation of duplex-phase microstructure in a forged Zr-2.5Nb alloy

  • Article
  • Published:
Science China Technological Sciences Aims and scope Submit manuscript

Abstract

Microstructural features of a duplex-phase Zr-2.5Nb alloy were investigated in detail using electron channeling contrast (ECC) imaging and electron backscatter diffraction (EBSD) technique in an emission gun scanning electron microscope (FEGSEM). The excellent resolution provided by the FEGSEM promises the combined utilization of both techniques to be quite adequate for characterizing the duplex-phase microstructures. Results show that the microstructure of the Zr-2.5Nb alloy is composed of bulk a grains (majority) in equiaxed or plate shape and thin β films (minority) surrounding the bulk grains, with their average grain size and thickness measured to be 1.4 µm and 72 nm, respectively. Analyses on α-grain boundaries reveal a number of low angle boundaries, most of which belong to deformation-induced dislocation boundaries. Measurements on relative proportions of various Burgers boundaries suggest very weak (if any) variant selection during β → α cooling, which should be related to deformation-induced higher nucleation rate of α phases. Compared to earlier attempts, more satisfactory indexing of fine β phases (down to nanoscale) is attained by the FEGSEM-based EBSD. Examples are presented to clearly reveal well-obeyed Burgers orientation relationships between adjacent a and β phases. Finally, it is deduced that continuing application of the FEGSEM-based EBSD to duplex-phase Zr alloys could help clarify controversies like the deformation priority of the two phases.

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.

Similar content being viewed by others

References

  1. Zinkle S J, Was G S. Materials challenges in nuclear energy. Acta Mater, 2013, 61: 735–758

    Article  Google Scholar 

  2. Jeong Y H, Park S Y, Lee M H, et al. Out-of-pile and in-pile perfomance of advanded zirconium alloys (HANA) for high burn-up fuel. J Nucl Sci Technol, 2006, 43: 977–983

    Article  Google Scholar 

  3. Toffolon-Masclet C, Guilbert T, Brachet J C. Study of secondary intermetallic phase precipitation/dissolution in Zr alloys by high temperature-high sensitivity calorimetry. J Nucl Mater, 2008, 372: 367–378

    Article  Google Scholar 

  4. Cai S, Daymond M R, Holt R A. Deformation of high β-phase fraction Zr–Nb alloys at room temperature. Acta Mater, 2012, 60: 3355–3369

    Article  Google Scholar 

  5. Yang Z N, Zhang F C, Qu L, et al. Formation of duplex microstructure in Zr–2.3Nb alloy and its plastic behaviour at various strain rates. Int J Plasticity, 2014, 54: 163–177

    Article  Google Scholar 

  6. Yang Z N, Zhang F C, Liu F C, et al. Achieving high strength and toughness in a Zr-2.3Nb alloy by the formation of duplex microstructure. Mater Des, 2012, 40: 400–406

    Article  Google Scholar 

  7. Hiwarkar V D, Sahoo S K, Mani krishna K V, et al. Coarsening of second phase in a two-phase Zr–2.5Nb: On the role of phase boundaries. Acta Mater, 2009, 57: 5812–5821

    Article  Google Scholar 

  8. Hovington P, Pinard P T, Lagacé M, et al. Towards a more comprehensive microstructural analysis of Zr–2.5Nb pressure tubing using image analysis and electron backscattered diffraction (EBSD). J Nucl Mater, 2009, 393: 162–174

    Article  Google Scholar 

  9. Romero J, Preuss M, Quinta da Fonseca J. Texture memory and variant selection during phase transformation of a zirconium alloy. Acta Mater, 2009, 57: 5501–5511

    Article  Google Scholar 

  10. Yao M Y, Zhou B X, Li Q, et al. A superior corrosion behavior of zircaloy-4 in lithiated water at 360°C/18.6 MPa by beta-quenching. J Nucl Mater, 2008, 374: 197–203

    Article  Google Scholar 

  11. Kumar M K, Samajdar I, Venkatramani N, et al. Explaining absence of texture development in cold rolled two-phase Zr–2.5 wt% Nb alloy. Acta Mater, 2003, 51: 625–640

    Article  Google Scholar 

  12. Sahoo S K, Hiwarkar V D, Jain L, et al. Deformed microstructures of two-phase Zr–2.5Nb alloy: Effects of the second phase hardness. J Nucl Mater, 2010, 404: 222–230

    Article  Google Scholar 

  13. Cai S, Daymond M R, Khan A K, et al. Elastic and plastic properties of beta(Zr) at room temperature. J Nucl Mater, 2009, 393: 67–76

    Article  Google Scholar 

  14. Muránsky O, Daymond M R, Bhattacharyya D, et al. Load partitioning and evidence of deformation twinning in dual-phase fine-grained Zr–2.5%Nb alloy. Mater Sci Eng A, 2013, 564: 548–558

    Article  Google Scholar 

  15. Randle V. Electron backscatter diffraction: Strategies for reliable data acquisition and processing. Mater Charact, 2009, 60: 913–922

    Article  Google Scholar 

  16. Zaefferer S. A critical review of orientation microscopy in SEM and TEM. Cryst Res Technol, 2011, 46: 607–628

    Article  Google Scholar 

  17. Holt R A, Zhao P. Micro-texture of extruded Zr–2.5Nb tubes. J Nucl Mater, 2004, 335: 520–528

    Article  Google Scholar 

  18. Hiwarkar V D, Sahoo S K, Samajdar I, et al. Annealing of cold worked two-phase Zr-2.5 Nb-associated microstructural developments. J Nucl Mater, 2009, 384: 30–37

    Article  Google Scholar 

  19. Zaefferer S, Elhami N N. Theory and application of electron channelling contrast imaging under controlled diffraction conditions. Acta Mater, 2014, 75: 20–50

    Article  Google Scholar 

  20. Humphreys F J. Review-grain and subgrain characterisation by electron backscatter diffraction. J Mater Sci, 2001, 36: 3833–3854

    Article  Google Scholar 

  21. Chai L J, Luan B F, Gao S S, et al. Study of precipitate evolution and recrystallization of β-quenched Zr-Sn-Nb-Fe-Cr-Cu alloy during aging. J Nucl Mater, 2012, 427: 274–281

    Article  Google Scholar 

  22. Chai L, Chen B, Zhou Z, et al. A special twin relationship or a common Burgers misorientation between α plates after β quenching in Zr alloy? Mater Charact, 2015, 104: 61–65

    Article  Google Scholar 

  23. Jeong Y H, Lee K O, Kim H G. Correlation between microstructure and corrosion behavior of Zr-Nb binary alloy. J Nucl Mater, 2002, 302: 9–19

    Article  Google Scholar 

  24. Tewari R, Srivastava D, Dey G K, et al. Microstructural evolution in zirconium based alloys. J Nucl Mater, 2008, 383: 153–171

    Article  Google Scholar 

  25. Choo K N, Kang Y H, Pyun S I, et al. Effect of composition and heat treatment on the microstructure and corrosion behavior of Zr-Nb alloys. J Nucl Mater, 1994, 209: 226–235

    Article  Google Scholar 

  26. Burgers W G. On the process of transition of the cubic-body-centered modification into the hexagonal-close-packed modification of zirconium. Physica, 1934, 1: 561–586

    Article  Google Scholar 

  27. Chai L, Luan B, Zhang M, et al. Experimental observation of 12 α variants inherited from one β grain in a Zr alloy. J Nucl Mater, 2013, 440: 377–381

    Article  Google Scholar 

  28. Chai L, Luan B, Xiao D, et al. Microstructural and textural evolution of commercially pure Zr sheet rolled at room and liquid nitrogen temperatures. Mater Design, 2015, 85: 296–308

    Article  Google Scholar 

  29. Chun Y B, Battaini M, Davies C H J, et al. Distribution characteristics of in-grain misorientation axes in cold-rolled commercially pure titanium and their correlation with active slip modes. Metall Mater Trans A, 2010, 41A: 3473–3487

    Article  Google Scholar 

  30. Akhtar A. Basal slip in zirconium. Acta Metall, 1973, 21: 1–11

    Article  Google Scholar 

  31. Hughes D A, Hansen N. Exploring the limit of dislocation based plasticity in nanostructured metals. Phys Rev Lett, 2014, 112: 135504

    Article  Google Scholar 

  32. Chauvy C, Barberis P, Montheillet F. Microstructure transformation during warm working of beta-treated lamellar zircaloy-4 within the upper alpha-range. Mater Sci Eng A, 2006, 431: 59–67

    Article  Google Scholar 

  33. Daymond M R, Holt R A, Cai S, et al. Texture inheritance and variant selection through an hcp–bcc–hcp phase transformation. Acta Mater, 2010, 58: 4053–4066

    Article  Google Scholar 

  34. Gey N, Humbert M, Gautier E, et al. Study of the β→α variant selection for a zircaloy-4 rod heated to the β transus in presence or not of an axial tensile stress. J Nucl Mater, 2004, 328: 137–145

    Article  Google Scholar 

  35. Kumar N A P K, Szpunar J A. Ebsd studies on microstructure and crystallographic orientation of delta-hydrides in zircaloy-4, Zr-1% Nb and Zr-2.5% Nb. Mater Sci Eng A, 2011, 528: 6366–6374

    Article  Google Scholar 

  36. Cabibbo M, Zherebtsov S, Mironov S, et al. Loss of coherency and interphase α/β angular deviation from the Burgers orientation relationship in a Ti–6Al–4V alloy compressed at 800°C. J Mater Sci, 2013, 48: 1100–1110

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to BaiFeng Luan.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chai, L., Wang, S., Luan, B. et al. Electron backscatter diffraction investigation of duplex-phase microstructure in a forged Zr-2.5Nb alloy. Sci. China Technol. Sci. 59, 673–679 (2016). https://doi.org/10.1007/s11431-016-6019-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11431-016-6019-0

Keywords

Navigation