Page 29 - Failure Analysis Case Studies II
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16
200
- I I I I I I
H2O L
Bar diameter (mm)
800 r
I)
2 500
2 400
4 300
5 200
Fig. 9. Continuous cooling transformation diagram for the steel of the shaft [2]. Before quenching, the samples
were first heated at 900 "C for 4 h.
Fig. IO. Calculation of torsional moment.
dT = 2nk,?dr, (3)
where k, is the ultimate shear stress. The ultimate shear stress can be estimated from the empirical
expression [4]
k, = oTsil.6, (4)
