PSI - Issue 43

Arnab Bhattacharyya et al. / Procedia Structural Integrity 43 (2023) 35–40 Author name / Structural Integrity Procedia 00 (2022) 000 – 000

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0.14% can be accepted as a reasonable estimate. The fracture toughness of the IF steel estimated by the suggested procedures are found to be in good agreement with the value determined by critical fracture strain approach as proposed by Haggag et al. (1989, 1990). The fracture toughness of AISI 316LN stainless steel determined by the suggested approaches is found be in reasonable agreement with fracture toughness values of AISI 316L stainless steel reported in ASM Handbook (2001). The estimated fracture toughness values for the selected steels by the proposed critical fracture strain approaches are found to be within 5 percent of the values determined by conventional fracture toughness test following ASTM E1820, or the values estimated by Hahn and Rosenfield relation (1968) or empirical relation given by Haggag et al.(1989, 1990). The fracture toughness values of the five selected commercial steels are summarized in Table 4. Table 4 Comparison of estimated fracture toughness (MPa.m 1/2 ) obtained by suggested methodologies and by other tests or approaches. Material Fracture toughness approaches Modified IEF Hahn-Rosenfield [1968] Following ASTM 1820 [2012].

Haggag et al. [1989,1990]

IF steel

209 464 484 242 321

262 505 544 248 346

177

—

316LN SS 304LN SS 0.14%C steel SA333 steel

— —

 434#

507

256* 341**

 190 (0.22%C)

364 (LC – orientation)#

#- Present estimation,* d = 2 × Grain diameter; ** d = 3 × Grain diameter 5. Conclusions

A modified principle has been suggested to estimate fracture toughness of structural materials by ball indentation technique. A critical value of true plastic strain representative to the true fracture strain obtained from uniaxial tensile test was used as the criteria of fracture. Fracture toughness (K CBIT ) values of AISI 304LN and SA333 have been estimated by the developed procedure and that obtained by standard J-integral test following ASTM standard are in excellent agreement. The estimated fracture toughness values of AISI 316LN, IF steel and 0.14% C steel appears to be rational when compared with the reported values of similar materials. References ASM Metal Hand Book, 2001, Fatigue and Fracture, ASM, 19, 857. Byun, T.S., Kim, J.W., Lee, B.S., Kim, I.S. and Hong, J.H., 2000, Estimation of fracture toughness transition curves of RPV steels from ball indentation and tensile test data, J. Nucl. Mater., 277, 263-273. Chatterjee, S., Panwar, S., Madhusoodanan, K., Rama Rao, A., 2016, Estimation of fracture toughness of Zr 2.5% Nb pressure tube of Pressurised Heavy Water Reactor using cyclic ball indentation technique, Nucl. Engg., Design, 305, 9 – 17. Ghosh, S., Tarafder, M., Sivaprasad, S., Tarafder, S., 2010, Experimental and numerical study of ball indentation for evaluation of mechanical properties and fracture toughness of structural steel, Trans. Ind. Inst. of Metals, 63, 617-622 Haggag, F.M., Nanstad, R.K., 1989, Estimating Fracture Toughness Using Tension or Ball Indentation Tests and a Modified Critical Strain Model”, Innovative Approaches to Irradiation Damage, and Fracture Analysis, Am. Soc. Mech. Engg., 170, 41-46. Haggag, F. M., Nanstad, R. K., Hutton, J. T., Thomas, D. L., and Swain, R. L., 1990, Use of Automated Ball Indentation to Measure Flow Properties and Estimate Fracture Toughness in Metallic Materials, in Applications of Automation Technology to Fatigue and Fracture Testing, ASTM 1092, A. A. Braun, N. E. Ashbaugh, and F. M. Smith, Eds., ASTM, Philadelphia, 188-208. Haggag, F.M., Byun, T.S., Hong, J.H., Miraglia, P.Q. and Murty, K.L., 1998 “Indentation -energy-to-fracture (IEF) parameter for characterization of DBTT in carbon steels using nondestructive automated ball indentation (ABI) technique”, Scr. Mater., 38, 645-651. Hahn, G.T., and Rosenfield, A.R., 1968 ASTM STP 432, Philadelphia, pp.5, 1968. Jeon, S.W., Lee, K.W., Kim, J.Y, Kim, W.J., Park, C.P., Kwon, D., 2017, Estimation of Fracture Toughness of Metallic Materials Using Instrumented Indentation: Critical Indentation Stress and Strain Model, Experimental Mechanics 57, 1013 – 1025. Lee, J.S., Jang, J., Lee, B. W., Choi,Y., Lee, S.G., Kwon, D., 2006, An instrumented indentation technique for estimating fracture toughness of ductile materials: A critical indentation energy model based on continuum damage mechanics, Acta Mater., 54, 1101-1109 Li, J., Li, F., Ma, X., Wang, Q., Dong, J., Yuan, Z., 2015A strain-dependent ductile damage model and its application in the derivation of fracture toughness by micro-indentation, Mater.Design, 67 623 – 630 Murty, K.L., Miraglia, P.Q., Mathew, M.D., Shah, V.N., Haggag, F.M., 1998, Nondestructive determination of tensile properties and fracture toughness of cold worked A36 steel, Int. J. Press. Vessel Piping, 75, 831-840. Ray, K. K., Dutta, A. K., 1999, Comparative Study of Indentation Fracture Toughness Evaluations of Soda-Lime-Silica Glass, Brtish Ceram Trans., 98, 165-171 Kruzic, J.J., Kim, D.K., Koester, K.J., Ritchie, R.O., 2009, Indentation techniques for evaluating the fracture toughness of biomaterials and hard tissues, J.Mech. Beha. Biomed. Mater., 2, 384-395 Quinn, G.D., Bradt, R.C., 2007. On the Vickers Indentation Fracture Toughness Test, J. Am. Ceram. Soc., 90, 673-680. Timofeev, B.T., Blumin, A.A., Anikovsky, V.V., 1998, Fracture toughness of low carbon steels and their weldments, Int. J. Press. Vess. Piping, 75, 945 – 950