PSI - Issue 19

T. Kato et al. / Procedia Structural Integrity 19 (2019) 238–248

243

6

Author name / Structural Integrity Procedia 00 (2019) 000 – 000

 r  (MPa)

Fig. 7. Shear stress  r  distribution at the cross-section of the B38 wheel with the center contact position.

σ r

σ z τ zr

σθ

τ r θ

τθ z

500

0

-500

-1000

Stress (MPa)

-1500

0

10

20

30

40

Moving distance (mm)

Fig. 8. Stress histories at the subsurface in the center contact position of the B38 wheel with rolling contact (r: radial direction,  : circumferential direction and z: axial direction).

3.2. Stress distribution and variation with tread braking An example of temperature distribution of the wheel rim during tread braking obtained from the heat transfer analysis is shown in Figure 9. It shows the temperature distribution when the wheel temperature is elevated to maximum at the area near the tread surface. Examples of contact pressure distribution at the tread surface of the wheel model with the rail model during tread braking and after cooling are shown in Figure 10. The contact pressure distributions and the maximum contact pressures are almost the same during braking and after cooling. The variation of stress components during the tread braking and the wheel rolling at the subsurface is shown in Figure 11. The variations of  r  and each of the normal stress components show the multiaxial stress states and are approximately the same as the results without tread braking.