PSI - Issue 48

Mirza Manjgo et al. / Procedia Structural Integrity 48 (2023) 161–168 Manjgo et al / Structural Integrity Procedia 00 (2023) 000 – 000

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Figure 10. CTOD resistant curve for specimen 500-51

4. Conclusion Steel SA500, high-strength steel, is a material used for military purposes due to its anti-ballistic protection. Its main function is the ability to deform, repel and absorb bullet energy. We characterized the material with basic experiments and proved its extremely high performance. Through the tensile test, we obtained its basic mechanical characteristics R m = 1613 MPa, R p0.2 = 1437 MPa, A 5 = 12.49 %. Through the impact test, we obtained the total impact energy E t = 25 J, the energy required for initiation E i = 11.7 J and the energy for propagation E p =13.2 J. With this test, we obtained the percentage of ductile fracture of the samples of about 32 %. By measuring the hardness HV10 and converting it to HB, we obtained satisfactory values (492 HB) - the prescribed hardness of the manufacturer is 480-520 HB. With the fracture mechanics test, we obtain material resistance curves and approximately the same J-integral (39.39 kJ/m 2 ),  Ic (0.0136 mm) and K JIc (96,27 MPa∙m 1/2 ) values. References [1] SIJ Acroni, PROTAC, Protection and Safety Performance [2] Bernetič, J., Kosec, G., Ažman, S., Marčetič, M., Podlipec, B., Kosec, B., Nagode, A., Kosec, L., Gojić, M., Rimac, M., Beganović, O., Burzić, Z., Vodopivec, F., Tomažič, I., 2014, PROTAC 500 – Armored steel of new generation, 10th Scientific/Research Symposium with International Participation „METALLIC AND NONMETALLIC MATERIALS“, Bugojno, BiH, 24.-25. [3] Mijatović, T., Manjgo, M., Burzić, M., Čolić, K., Burzić, Z., Vuherer, T. 2019, Structural integrity assessment from the aspect of fracture mechanics, Structural Integrity and Life, Vol. 19(2), 121 – 124 [4] Burzić, Z., Sedmak, S., Manjgo, M ., 2001, Experimental evaluation of weldment fracture mechanics parameters (in Serbian), Structural Integrity and Life, Vol. 1, 97-105 [5] Lešnjak, M., Kosec, B., Karpe, B., Janjić, G., Gojić, M., Bernetič, J., 2021, Kosec, “Thermal properties of armour steel PROTAC 600”, DEMI 2021, 15th International Conference on Accomplishments in Mechanical and Industrial Engineering Banja Luka 28 – 29 May 2021.