Commercially pure Fe and Ni have been diffusion bonded. Pure Cu (99.999%) and Au-20Sn eutectic alloys have been used to bond Fe while Cu has been used to bond Ni. Fe bonded using Cu at 1071 °C for 10 h showed ∼20 μm thick residual Cu in the bond centerline. However, at 1100°C bonding temperature for 10 h the residual Cu disappeared and the Cu content of the joint centerline was ∼7wt.%. Although Sn forms intermetallics with both Fe and Au, no intermetallics were found when Au-20Sn eutectic was used to bond Fe at 600-650°C for 10h. Ni bonded at 1071°C for 10h contained 40 wt.% Cu in the joint centerline with the Cu content decreasing gradually with increasing distance from the bondline. Cu content in the bond centerline decreased to 35wt.% at 1100°C for 10 h. The concentration profiles of Cu in a Ni-Cu diffusion couple were simulated with DICTRA/Thermocalc The simulated profiles were comparable to the experimental profiles. The ultimate tensile strengths obtained for Fe-Cu system were 245 and 276 MPa at 1085±1 and 1090±1°C for 10 h, respectively.