Advertisement

Springer Nature is making Coronavirus research free. View research | View latest news | Sign up for updates

Fracture Characterization of Steels by Means of the Small Punch Test

  • 506 Accesses

  • 22 Citations

Abstract

A hot rolled API X-70 steel plate and its heat-affected zone (the region with the maximum hardness and lowest toughness of the welded joint made using this steel) were employed to obtain the material’s room temperature elasto-plastic fracture toughness, JIc, by means of small punch tests (SPTs) using both conventional un-notched samples and longitudinally-notched SPT specimens. In the latter case, the notches were manufactured by micromachining different notch depth-to-thickness ratios (a/t = 0.3 and 0.4). The representative toughness parameter used with the conventional SPT tests was the maximum strain measured directly in the failed region, while in the case of the notched samples, the consumed energy until the initiation of a crack from the tip of the notch was considered the most useful parameter of choice. The onset of crack initiation was determined directly from the load-displacement plot of each test with the aid of scanning electron microscope observations performed on different samples over which interrupted tests had been conducted. These tests were interrupted at different percentages of the maximum registered load. A simple correlation between the energy consumed until the initiation of crack growth in the notched SPT sample and the critical J value obtained using standard tests (J-R curves) was determined, defining an easy and promising way to derive fracture toughness from miniature SPT tests.

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

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10

References

  1. 1.

    Fleury E, Ha JS (1998) Small Punch test to estimate the mechanical properties of steels for steam power plant: I Mechanical Strength. Int J Press Vessel Pip 75:699–706

  2. 2.

    Vorliceck V, Exworthy LF, Flewitt PEJ (1995) Evaluation of a miniaturized disc test for establishing the mechanical properties of low-alloy ferritic steels. J Mater Sci 30:2936–2943

  3. 3.

    Finarelli D, Roeding M, Carsughi F (2004) Small punch tests on austenitic and martensitic steels irradiated in a spallation environment with 530 MeV protons. J Nucl Mater 328:146s–150s

  4. 4.

    Kameda J, Mao X (1992) Small punch and TEM-disc testing techniques and their application to characterization of radiation damage. J Mater Sci 27:983–989

  5. 5.

    Rodríguez C, García CJ, Cárdenas E, Belzunce FJ, Betegón C (2009) Mechanical properties characterization of heat-affected zone using the small punch test. Weld J 88:188–192

  6. 6.

    Contreras MA, Rodríguez C, Belzunce FJ, Betegón C (2008) The use of small punch test to evaluate the ductile to brittle transition temperature of structural steels. Fatigue Fract Eng Mater Struct 31:727–737

  7. 7.

    Mao X, Takahashi H, Kodaira K (1992) Super small punch test to estimate fracture toughness, J1C and its application to radiation embrittlement of 2.25Cr-1Mo steels. Mater Sci Eng A 150:231–236

  8. 8.

    Shekhter A, Kim S, Carr DG, Croker ABL, Ringer SP (2002) Assessment of temper embrittlement in an ex-service 1Cr–1Mo–0.25V power generating rotor by Charpy V-Notch testing, KIc fracture toughness and small punch test. Int J Press Vessel Pip 79:611–615

  9. 9.

    Mao X, Takahashi H (1987) Development of a further miniaturized specimen of 3 mm diameter for TEM disk small punch tests. J Nucl Mater 150:42–52

  10. 10.

    Misawa T, Nagata S, Aoki N, Ishizaka J, Hamaguchi Y (1989) Fracture toughness evaluation of fusion reactor structural steels at low temperatures by small punch tests. J Nucl Mater 168:225–232

  11. 11.

    Saucedo-Muñoz ML, Liu SC, Hashida T, Takasashi H (2001) Correlationship between JIC and equivalent fracture strain determined by small-punch tests in JN1, JJ1 and JK2 austenitic stainless steels. Cryogenics 41:713–719

  12. 12.

    Bulloch JH (2004) A study concerning material fracture toughness and some small punch test data for low alloy steels. Eng Fail Anal 11:635–653

  13. 13.

    CEN/WS21 (2006) Small punch test method for metallic materials. Part B: a code of practice for small punch testing for tensile and fracture behavior

  14. 14.

    ASTM E1820 (1999) Standard test method for measurement of fracture toughness, ASTM

  15. 15.

    Cárdenas E (2010) Fracture behaviour characterization of a pipeline Steel by means of Small Punch Test. Ph. D. Thesis, Universidad de Oviedo

  16. 16.

    Suzuki M, Eto M, Fukaya D, Nishiyama Y, Kodaira T, Oku T, Adachi M, Umino A, Takahashi I, Misawa T, Hamaguchi Y (1991) Evaluation of toughness degradation by small punch (SP) tests for neutron-irradiated 2.25Cr-1Mo steel. J Nucl Mater 179–181:441–444

  17. 17.

    Budzakoska E, Carr DG, Stathers PA, Li H, Harrison RP, Hellier AK, Yeung WY (2007) Predicting the J integral fracture toughness of Al 6061 using small punch testing. Fatigue Fract Eng Mater Struct 30–9:796–807

  18. 18.

    Anderson TL (2004) Fracture mechanics. Fundamentals and applications 3th edition, 2005

  19. 19.

    Cuesta II, Alegre JM, Lacalle R, Alvarez JA, Gutierrez-Solana F (2008) Calculating J-integral over SPT samples to estimate the fracture toughness; Anales de Mecánica de la Fractura, 25, Vol II, 486–491

  20. 20.

    Ju JB, Jang JI, Kwon D (2003) Evaluation of fracture toughness by small-punch testing techniques using sharp notched specimens. Int J Press Vessel Pip 80:221–228

Download references

Acknowledgments

The authors are grateful for the financial support for this study provided by the Ministerio de Ciencia e Innovación of Spain, through project MAT2008-06879-C03-01.

Author information

Correspondence to C. Rodríguez.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Rodríguez, C., Cárdenas, E., Belzunce, F.J. et al. Fracture Characterization of Steels by Means of the Small Punch Test. Exp Mech 53, 385–392 (2013). https://doi.org/10.1007/s11340-012-9637-x

Download citation

Keywords

  • Fracture
  • API steels
  • Small Punch Test
  • Heat Affected Zone