"The Energy Dispersive X-ray Spectroscopy (EDX) study suggests that element migration between the metals occurred during the manufacturing process; the pressure rolling, twisting, and hammer welding of iron and steel laminates produced essentially a mono-metal."
I have to believe that the gen-u-ine Metallurgical Engineer would retract or reconsider that statement if he took a moment to think about his choice of words. If the process of rolling, twisting, hammering, and welding of iron and steel resulted in "essentially a mono-metal", then we would expect to see a mono-coloration after blueing and etching, i.e., no difference. There is still a significant enough difference between the layers that we can see, and sometimes even feel, the difference between the iron and steel. It is the contrast which we so frequently discuss and admire. Certainly, there is amalgamation and fusion within the weld joints.
