Dear Yazdan. To calculate the shear stress you need to applied the following formulas:

1) The cutting force projection in shear plane is => Fc * cos phi

2) The shear area is the chip tickness multiplied by width of cut, this is (t0/sin phi) * width of cut

3) Finally, you need to divide 1) by 2) and obtained the shear stress.

Thanks Dear Daniel. I am familiar with this equation, however I was interesting to know if I can measure shear stress by using field output request in ABAQUS.

Thanks again.

Sorry Yasdan. I think that you want to compare values take from software and by phisical model.