PSI - Issue 68

Ema Kukuljan et al. / Procedia Structural Integrity 68 (2025) 822–827 E. Kukuljan et al. / Structural Integrity Procedia 00 (2025) 000–000

826

5

6. Analysis and results The calibrated model was used to simulate the quenching of 42CrMo4 cylindrical steel specimen (Ø90 × 200 mm) austenitized at 850°C and quenched in stationary mineral oil at 20°C, with measured hardness data available in Smoljan et al. (2015). Parameters of 42CrMo4 steel were taken as ρ = 7850 kg/m 3 and c = 460 J/kgK. Chemical composition of steel 42CrMo4 is given in Table 1.

Table 1. Chemical composition (wt.%) of steel 42 CrMo4 from Smoljan et al. (2015) Material C Si Mn P S Cr

Mo

0,23

42CrMo4

0,42

0,21

0,63

0,012

0,02

1,09

The central cross-section of the specimen with an overlay showing hardness distribution obtained with the developed numerical model is shown in Figure 5. Discrete points designated with numerals 1-9 denote locations on the specimen where hardness was measured and reported in Smoljan et al. (2015). A comparison of hardness values determined experimentally and by numerical simulation using a developed numerical model are provided in Table 2. Hardness values at individual measurement points are in good agreement with experimental results and the as quenched hardness distribution of steel specimen was successfully estimated.

54,9

49,4

43,9

38,4

32,9

Fig. 5. Hardness distribution obtained using the developed numerical model with marked discrete points i.e. nodes where hardness measurements were evaluated

Table 2. Numerically and experimentally determined values of Rockwell hardness

Hardness (Measured)

Difference (HRC)

Difference (%)

Hardness (Model)

Node number

1 2 3 4 5 6 7 8 9

33,1 34,3 45,7 35,3 45,7 40,5 34

33 34 49 33 35 49 37 45 51

0,1 0,3 3,3 0,3 3,3 3,5 1

0,3 0,9 6,7 3,0 0,9 6,7 9,5 4,4 5,9

47 54

2 3