Nanoindentation induced deformation anisotropy in WC, β-si3n4 and ZrB2 crystals

Transcription

1 Engineering Conferences International ECI Digital Archives Nanomechanical Testing in Materials Research and Development V Proceedings Fall Nanoindentation induced deformation anisotropy in WC, β-si3n4 and ZrB2 crystals Tamas Csanadi, Slovak Academy of Sciences, tcsanadi@gmail.com Dusan Nemeth, Slovak Academy of Sciences Alexandra Kovalcikova, Slovak Academy of Sciences Jan Dusza, Slovak Academy of Sciences Follow this and additional works at: Part of the Materials Science and Engineering Commons Recommended Citation Tamas Csanadi, Dusan Nemeth, Alexandra Kovalcikova, and Jan Dusza, "Nanoindentation induced deformation anisotropy in WC, β- Si3N4 and ZrB2 crystals" in "Nanomechanical Testing in Materials Research and Development V", Dr. Marc Legros, CEMES-CNRS, France Eds, ECI Symposium Series, (2015). This Abstract and Presentation is brought to you for free and open access by the Proceedings at ECI Digital Archives. It has been accepted for inclusion in Nanomechanical Testing in Materials Research and Development V by an authorized administrator of ECI Digital Archives. For more information, please contact franco@bepress.com.

2 Nanoindentation induced deformation anisotropy in WC, β-si 3 N 4 and ZrB 2 crystals Tamás Csanádi, Dušan Németh, Alexandra Kovalčíková and Ján Dusza Institute of Materials Research, Slovak Academy of Sciences, Watsonova 47, Košice, Slovak Republic

3 Introduction

4 Introduction WC, β-si 3 N 4 and ZrB 2 : Famous ceramics WC, WC-Co initial development 1920s (WIDIA) β-si 3 N 4 golden age 80-90, but still fantastic ZrB 2 recently the new star Hexagonal crystallographic structure High hardness, great wear resistance, Anisotropy Improved mechanical properties by texturing cutting tools, WC-Co ball bearings, β-si 3 N 4 thermal protecting layers, ZrB 2

5 Introduction WC, β-si 3 N 4 and ZrB 2 : Famous ceramics WC, WC-Co initial development 1920s (WIDIA) β-si 3 N 4 golden age 80-90, but still fantastic ZrB 2 recently the new star Hexagonal crystallographic structure High hardness, great wear resistance, Anisotropy Improved mechanical properties by texturing cutting tools, WC-Co How do we orientate the grains?? ball bearings, β-si 3 N 4 DEFORMATION ANISOTROPY?? thermal protecting layers, ZrB 2

6 Aim

7 Aim Deformation anisotropy of WC, β-si 3 N 4, ZrB 2 crystals Nanoindentation: hardness and indentation modulus Theoretical prediction of the orientation dependence

8 Experimental

9 Experimental MATERIALS WC, β-si 3 N 4, ZrB 2 Coal mining grade WC-Co Reaction bonded Si 3 N 4 Spark plasma sintered ZrB 2

10 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation

11 Experimental MATERIALS WC, β-si 3 N 4, ZrB 2 Area selection Surface preparation SEM, EBSD METHOD

12 Experimental MATERIALS WC, β-si 3 N 4, ZrB 2 Area selection Surface preparation SEM, EBSD METHOD

13 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation SEM, EBSD Nanoindentation Berkovich tip, 900 indents, CSM mode, depth limit of 200 nm 30x30 indents

14 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation SEM, EBSD Nanoindentation AFM,SEM Surface morphology

15 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation SEM, EBSD Nanoindentation AFM,SEM Surface morphology 4 µm

16 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation SEM, EBSD Nanoindentation AFM,SEM Surface morphology, evaluation

17 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation SEM, EBSD Nanoindentation AFM,SEM Surface morphology, evaluation H avg E avg

18 Experimental MATERIALS METHOD WC, β-si 3 N 4, ZrB 2 Surface preparation SEM, EBSD Nanoindentation AFM,SEM Surface morphology, evaluation H avg (Φ,φ 2 ) E avg (Φ,φ 2 )

19 Results

20 Results Indentation modulus WC

21 Results Indentation modulus WC

22 Results Indentation modulus β-si 3 N 4

23 Results Indentation modulus β-si 3 N 4

24 Results Indentation modulus ZrB 2

25 Results Indentation modulus ZrB 2

26 Results Indentation modulus How could be the indentation modulus anisotropy predicted, E(Φ)?

27 Results Hardness WC

28 Results Hardness WC

29 Results Hardness β-si 3 N 4

30 Results Hardness β-si 3 N 4

31 Results Hardness ZrB 2

32 Results Hardness ZrB 2

33 Results Hardness How could be the hardness anisotropy predicted, H(Φ)?

34 Models

35 Models Elastic anisotropy How could be the indentation modulus anisotropy predicted, E(Φ)?

36 Models Elastic anisotropy How could be the indentation modulus anisotropy predicted, E(Φ)? How correlate to the elastic constants, c ij E(Φ)?

37 Models Elastic anisotropy Vlassak-Nix model Elastic constants, c ij FEM calculation J.J. Vlassak, W.D. Nix, J. Mech. Phys. Solids 42 (1994)

38 Models Elastic anisotropy Vlassak-Nix model Elastic constants, c ij FEM calculation conical indenter is assumed elastic constants C ijkl indentation modulus E (Φ) numerical calculations by Maple

39 Models Elastic anisotropy Vlassak-Nix model Elastic constants, c ij FEM calculation conical indenter is assumed elastic constants C ijkl Berkovich and conical indenters, h max =200 nm elastic constants C ijkl rotated C ijkl indentation modulus E (Φ) numerical calculations by Maple Oliver-Pharr method indentation modulus E (Φ) numerical calculations by ANSYS

40 Models Elastic anisotropy Vlassak-Nix model Elastic constants, c ij FEM calculation

41 Models Elastic anisotropy Vlassak-Nix model Elastic constants, c ij FEM calculation

42 Models Elastic anisotropy Vlassak-Nix model Elastic constants, c ij FEM calculation

43 Models Plastic anisotropy How could be the hardness anisotropy predicted, H(Φ)?

44 Models Plastic anisotropy No correlation between the indentation modulus and the hardness anisotropy!

45 Models Plastic anisotropy Do brittle ceramics show plasticity at nano-scale?

46 Models Plastic anisotropy Do brittle ceramics show plasticity at nano-scale?

47 {10-10}<11-23> Models Plastic anisotropy Main slip systems: Single crystal macroindnetation - TEM M.K. Hibbs, R. Sinclair, Acta Metall. 29 (1981) 1645.

48 Models Plastic anisotropy Main slip systems: Single crystal macroindnetation - TEM {10-10}<11-23> {10-10}[0001] M.K. Hibbs, R. Sinclair, Acta Metall. 29 (1981) X. Milhet, H. Garem, J.L. Demenet, J. Rabier, and T. Rouxel, J. Mater. Sci. 31 (1997)

49 Models Plastic anisotropy Main slip systems: Single crystal macroindnetation - TEM {10-10}<11-23> {10-10}[0001] {10-10}<11-20> M.K. Hibbs, R. Sinclair, Acta Metall. 29 (1981) X. Milhet, H. Garem, J.L. Demenet, J. Rabier, and T. Rouxel, J. Mater. Sci. 31 (1997) J.S. Haggerty JS, D.W Lee, J. Am. Ceram. Soc. 54 (1971)

50 Models Plastic anisotropy Main slip systems: Micropillar compression - SEM {10-10}<11-23> {10-10}[0001] {10-10}<11-20> M.K. Hibbs, R. Sinclair, Acta Metall. 29 (1981) {10-10}<11-23> X. Milhet et al., J. Mater. Sci. 31 (1997) J.S. Haggerty JS, D.W Lee, J. Am. Ceram. Soc. 54 (1971) T. Csanádi et al., J. Eur. Ceram. Soc. 34 (2014)

51 Models Plastic anisotropy Main slip systems: Micropillar compression - SEM {10-10}<11-23> {10-10}[0001] {10-10}<11-20> M.K. Hibbs, R. Sinclair, Acta Metall. 29 (1981) X. Milhet et al., J. Mater. Sci. 31 (1997) J.S. Haggerty JS, D.W Lee, J. Am. Ceram. Soc. 54 (1971) {10-10}<11-23> {10-10}[0001] T. Csanádi et al., J. Eur. Ceram. Soc. 34 (2014) T. Csanádi et al., J. Am. Ceram. Soc. 98 (2015)

52 Models Plastic anisotropy Main slip systems: Micropillar compression - SEM {10-10}<11-23> {10-10}[0001] {10-10}<11-20> M.K. Hibbs, R. Sinclair, Acta Metall. 29 (1981) X. Milhet et al., J. Mater. Sci. 31 (1997) J.S. Haggerty JS, D.W Lee, J. Am. Ceram. Soc. 54 (1971) {10-10}<11-23> {10-10}[0001] {10-10}<11-23> T. Csanádi et al., J. Eur. Ceram. Soc. 34 (2014) T. Csanádi et al., J. Am. Ceram. Soc. 98 (2015) T. Csanádi et al., J. Am. Ceram. Soc. (2015) submitted.

53 Models Plastic anisotropy How correlate the H(Φ) to the slip systems?? {10-10}<11-23> {10-10}[0001] {10-10}<11-20> {10-10}<11-23>

54 Idea: Models Plastic anisotropy Easy slip model plastic deformation is controlled by slip activation mean stress/hardness depends on the position of the slip system relative to the acting force stress field is not uniaxial!!

55 Idea: Models Plastic anisotropy Easy slip model plastic deformation is controlled by slip activation mean stress/hardness depends on the position of the slip system relative to the acting force stress field is not uniaxial!! Assumptions: conical indenter perpendicular elementary force and homogeneous stress field close to the indenter dislocation glide is the possible slip systems no strain hardening m(φ,φ) m avg,φ (Φ)

56 Idea: Models Plastic anisotropy Easy slip model plastic deformation is controlled by slip activation mean stress/hardness depends on the position of the slip system relative to the acting force stress field is not uniaxial!! Assumptions: conical indenter perpendicular elementary force and homogeneous stress field close to the indenter dislocation glide is the possible slip systems no strain hardening m(φ,φ) m avg,φ (Φ) T. Csanádi et al., Acta Mater. 83 (2015)

57 Models Plastic anisotropy Easy slip model {10-10}<11-23> T. Csanádi et al., Acta Mater. 83 (2015)

58 Models Plastic anisotropy Easy slip model {10-10}[0001]

59 Models Plastic anisotropy Easy slip model {10-10}<11-23> {10-10}<11-20>

60 Summary

61 Summary Anisotropic deformation behavior of WC, β-si 3 N 4 and ZrB 2 ceramic crystals has been investigated by nanoindentation. The most significant factor on the orientation dependence of hardness and indentation modulus is the Φ rotation angle from the basal towards the prismatic direction. The elastic and plastic anisotropy could be predicted theoretically on the basis of the single crystal elastic constants and the activated slip systems, respectively.

62 Acknowledgements Supervisor: prof. RNDr. Ján Dusza, DrSc. Colleagues from Slovakia: prof. RNDr. Pavol Šajgalík, DrSc. doc. Ing. Zoltán Lenčéš, PhD. Ing. Dušan Németh RNDr. Pavol Hvizdoš, CSc. Colleagues from Hungary: Dr. Nguyen Q. Chinh Szommer Péter Dr. Havancsák Károly Varga Gábor Colleagues from United Kingdom: prof. Mike Reece Salvatore Grasso, PhD.

63 Thank you for your attention!