Why internal stress distribution is different between a circular and rectangular object

[student85]

Hi, currently i'm having question regarding the internal stress distribution for circular and rectangular shape soild. May i ask why
their internal stress distribution is different? Is it because the inner sturcture or composition of the soild is different? Or is it their calculation of stress is different? Please kindly advice

Thanks

[Enthalpy]

It's because the temperature profile during cooling (possibly quenching) depends on the shape.