PSI - Issue 43

Pavel Doubek et al. / Procedia Structural Integrity 43 (2023) 101–106

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Pavel Doubek et al./ Structural Integrity Procedia 00 (2022) 000 – 000

when approaching the interphase (approx. -0.2 mm). The passage of HAZ (between 0.2 – 0.8 mm) and stabilization near nominal values of the substrate follows. The Young's modulus values of the upper part of the cladded layer (mostly pure aluminum bronze or hard chrome) are partially getting closer to the values taken from the material sheets. The values for Metco 51NS (at a distance of about -2.0 mm from the interface) deviate by 6.7 - 13.3%. The values for Rockit 401 (at a distance of about -1.8 mm from the interface) deviate by 7.9% (Set1) and by 34.8% (Set2). There are smaller differences due to the processing technology. More significant differences can be caused by inhomogeneity of the material near the surface as well (inclusions, impurities, partial mixing of the molten materials, etc.). At the interface (between -0.2 to 0.2 mm) of aluminum bronze and S960, a significant increase in Young's modulus values is evident. On the other hand, there is an evident decrease at the interface of hard chrome and S960. The passage of HAZ (between 0.2 – 1.2 mm) and stabilization near nominal values of the substrate follows. The calculated values of Young's modulus near the substrate for both types of applications, which are between 191 and 202.5 GPa, correspond to the declared value of 202 GPa. 4. Conclusions Vickers microhardness was measured in the vicinity of the bi-metal interface. Based on a course of microhardness, the approximate Young's modulus was calculated. According to the obtained results, it can be concluded that the structure of a material with bi-metal interface can be divided into five phases (Fig. 4b) which have an influence on the course of microhardness – surface layer, bonding zone, close vicinity of interface, heat-affected zone and substrate. Changes in the microhardness during the transition through these layers have an impact on the changes of the fracture mechanical properties. The course of microhardness and Young's modulus have been influenced by the chosen technology of cladding and subsequent machining as well. Acknowledgements Financial support from the Faculty of Civil Engineering, Brno University of Technology (project No. FAST-S-22 7881), and from a project of the Czech Science Foundation - Influence of Material Properties of High-Strength Steels on the Durability of Engineering Structures and Bridges (project No. 21-14886S) are gratefully acknowledged. References Bhat, S., Adarsha, H., Ravinarayan, V., Koushik, V.P., 2019. Analytical model for estimation of energy release rate at mode I crack tip in bi material of identical steels joined by an over-matched weld interlayer. Procedia Structural Integrity 7, 21 – 28. Doubek, P., Malíková, L ., Miarka, P., Seitl, S., 2022. Analysis of the material properties in the vicinity of bi-material interface made by the laser cladded protective layer on the S960. ECF23 Conference Series: Materials structure and micromechanics of fracture, submitted. Hardchrome Engineering Pty Ltd, Homepage - Hardchrome Engineering [online, 22.3.2021]. Available from: https://hardchrome.com.au/wp content/uploads/2021/11/HC-Plating.pdf. H aušild , P., Materna, A., Kocmanová, L. , Matějíček, J., 2016. Determination of the individual phase properties from the measured grid indentation data. Journal of Materials Research, Vol 31 (22), pp. 3538 – 3548. H ö ganas AB, Homepage – H ö ganas AB [online 20.9.2022]. Available from: https://www.hoganas.com/en/powder technologies/products/rockit/rockit-401. Kocmanová, L., Haušild , P., Materna, A., Matějíček, J., 2015. Investigation of Indentation Parameters Near the Interface between Two Materials. Key Engineering Materials, Vol. 662, pp. 31 – 34. Laser Therm s.r.o. Homepage – Laser Therm s.r.o. [online, 8.5.2022]. Available from: https://www.lasertherm.cz/eng/technologies/laser technologies/laser-cladding. Li, M., Han, B., Song, L., He, Q., 2020. Enhanced surface layers by laser cladding and ion sulfurization processing towards improved wear resistance and self-lubrication performances. Applied Surface Science 503, 144226. Malíková, L., Miarka, P., Doubek, P., Seitl, S., 2022. Influence of the interphase between laser-cladded metal layer and steel substrate on the fatigue propagation of a short edge crack, Frattura ed Integrita Strutturale, Vol. 59 (2022), pp. 514 – 524. Oerlikon Metco Europe GmbH, Homepage - Oerlikon Metco Europe GmbH [online 20.9.2022]. Available from: https://mymetco europe.oerlikon.com/en-us/product/metco51ns Optics.org [online, 8.5.2022]. Green laser alternative to prohibited hard chrome plating. Available from: https://optics.org/news/8/8/26 Tabor, D. 1951. Hardness of Metals, Clarendon Press, Oxford Classic Series 2000 Zhu, L., Xue, P., Lan, Q., Meng, G., Ren, Y., Yang, Z., Xu, P., Liu, Z., 2021. Recent research and development status of laser cladding: A review. Optics & Laser Technology 138, 106915.