1) Nitrogen (N) is diffusing into a semi-infinite bar of BCC iron (Fe) with an initial N concentration of 0.1 wt% at 1000 C. What depth from the surface will have a concentration of 1.5 wt% N after 1 hour if the imposed surface concentration is 50 wt% N. Interpolation required

2) A rectangular rod with a length of 1.4 m, thickness of 2 cm and width of 3 cm is to be used under tensile loading conditions. The rod is made out of a metal with a yield strength of 75 MPa, tensile strength of 300 MPa and an elastic modulus of 110 GPa. Calculate the maximum working force that the rod can withstand in tension WITHOUT deforming if the factor of safety of 5 is used.