PSI - Issue 59

Olexandr Ivanov et al. / Procedia Structural Integrity 59 (2024) 622–628 Olexandr Ivanov et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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According to the XRD analysis of sample 2 (Fig. 2, a) in its structure there are traces of BMo, Fe 2 B, TiC and BMo with most significant deviations in crystal parameters which is the result of dissolving of other elements, which corresponds with prolonged crystals in the structure of sample 2 (Fig 1, b). Results of XRD analysis of sample 3 (Fig. 2, b) shows presence of Fe(Mo, B) 2 (polygonal crystals), TiC (round-like grains centered in Fe(Mo, B) 2 ), Fe 2 B, and ferrite.

Fig. 2. XRD patterns of hardfacing samples 2 (a) and 3 (b).

Hardness value of tested hardfacing as follows, HRC: 49 sample 1, 59 sample 2, 64 sample 3, 63 sample 4. Fig. 3 shows relative abrasive wear resistance of experimental hardfacings and hardfacing made with serial production electrodes with different abrasive impact. As can be seen hardfacings of samples 3 and 4 show decent wear resistance in condition of fixed abrasive impact, as well as sample 3 shows the highest wear resistance in condition of non-fixed abrasive impact. This values is a result of Fe(Mo, B) 2 phase presence in increased amount in the structure. As for impact-abrasive load WC containing hardfacing from serial T3 electrode shows the highest wear resistance, followed by serial Super 20 and samples 2, 4, while sample 3 shows slightly lesser resistance. In order of high hardness and high wear resistance value samples 3 and 4 look like a perspective materials for implementing for production. On the other hand, technological parameters of samples 3 and 4 differs: welding process of sample 3 characterized with stable arc burning and decent coherence between main material and substrate as well as an absence of defects; welding with 4 is complicated with unstable arc burning, fusion zone and hardfaced material characterized with presence of defects (Fig. 4).

Fig. 3. Comparative wear resistance tests in condition of fixed (a), non-fixed (b) abrasive and impact-abrasive loads, where electrodes: 1 – Lastek 2400 (Belgium), 2 – Hardalloy 155 (USA), 3 – Super 20 (Sweden), 4 – T3 (Ukraine), 5 – sample 1, 6 – sample 2, 7 – sample 3, 8 – sample 4.