PSI - Issue 59

Olexandr Ivanov et al. / Procedia Structural Integrity 59 (2024) 330–336 Olexandr Ivanov et al. / Structural Integrity Procedia 00 (2019) 000 – 000

331

2

Keywords: 3D modeling; hardfacing; microstructure; flux-cored arc welding; hardness

1. Introduction Researching and investigation of the wear-resistance materials is one of the main problems of material science. Restoring and increasing the durability is an actual problem because the failure of the vast majority of details and elements of the construction of many machining and production industries is characterized by the wearing of only a small volume of working material. That is why, in most cases, restoring is more practical than using new details. On the other hand, increasing the durability of working surfaces before their exploitation could highly increase its working resources and lead to a reduction in a number of overhaul periods. Hardness, crack resistance and resistance at different working condition is highly important for wear resistance materials. Wear with friction is one of the most intensive mechanisms of wear. Depending on the working condition, wear is usually divided into a few categories, such as wearing with fixed, non-fixed, gas abrasive and impact abrasive action. But, usually, wear of detail with strictly one single wear mechanism is rare, and wear is the result of combination of the above mentioned mechanisms. Therefore, the complex research on the durability of the material, which considers the different mechanisms of wear, is highly important. Such research is long-lasting and responsible. Because the material properties depend on many factors, nowadays, besides only mechanical methods of research, important, perspective and still relatively new are such methods as mathematical modeling of development (Trembach et al. (2022)), thermodynamic modeling (Shihab et al. (2020)), approximation modeling for prediction of mechanical properties with ab initio prediction (Prysyazhnyuk et al. (2021)), finite element method such as PRISM-Plasticity (Yaghoobi et al. (2019)), optimization of technological parameters (Bembenek et al. (2022), Ropyak et al. (2023), Buketov et al. (2016)), using thermography for special material investigation (Bembenek and Uhrynski (2022)) and others. There is also 3D-modeling that widely expands the researching of different materials and helps to investigate the features of their structures (Eshlaghi et al. (2023), Wang et al. (2023)) but the disadvantages of such modeling are that the actual models are based on mathematical calculation and approximation, which only approximate the structure geometry and relief to the real values. Also, as a perspective one, there is the direction of research of the microstructure with 3D models based on experimental data. Such research could merge experimental and theoretical/virtual data for more precise and complex prediction of material behaviour in different working conditions. Structure features, distribution of strengthening phases in the structure, geometry and form of particles are highly important for the material durability in the different working conditions. So, therefore, the investigation of the structure in three-dimension is as important as two-dimensional research. For the present research, the flux-cored arc welding (FCAW) hardfacing was chosen as a simple and productive, widely used method for restoring and increasing the durability of details (Ivanov et al. (2020)) as well as the Fe-Ti Mo-B-C system was chosen in accordance to its high hardness and mechanical parameters. 2. Methods and materials 2.1 Development of research sample As a research material hardfacing coating welded with a powder electrode on the 08 kp steel (DSTU EN 10139:2019) was used. Flux-cored powder filler was carried out as mixed of fine initial components, at. %: 8.26 Ti. 8.26 Mo, 22.01 B, 5.51 C, rest – Fe. Width and height of the electrode is 8  2,5 mm, electrode length is 420 mm. Welding was carried out in manual mode with direct current of 150 A, around 30 V, reverse polarity. The substrate material for welding was steel 40 (DSTU 7809:2015) strip 10  10 mm. Cooling was carried out with 20 C° at air. Hardfacing was made in three layers in order to ensure a higher amount of deposited material during structure investigation. Images of the structure were obtained with a digital camera attached to the PMT-3 hardness meter lens. Hardness was measured with Rockwell C scale. For modeling of a three-dimensional model of the structure particle images, obtained with the special invented algorithm, free software Blender was used as Image Pro Plus software was used for additional images processing and measurements.