Remote laser cutting of high cobalt content electrical steel: preliminary results and microscopy

We present initial results from trials of cutting thin sheets of high Cobalt content electrical steel with a remote laser for the production of electric machine laminations. Cuts in 0.15 mm high-cobalt (Hiperco®50) steel samples were produced at various scan speeds and powers. Microscopy carried out on the sample cross-sections showed two distinct layers at the boundary of the kerf, each with a different microstructure to the bulk material. It is proposed that these are a heat affected zone and a layer of resolidified molten material. It was shown that fluence was the dominant parameter in influencing cut depth, although some variation with interaction time was noted., particularly with respect to cut morphology.