The Influence of Er Element Content on the Structure, Amorphous State and Performance of a Laser Clad Fe-based Amorphous Coating
C-M. Cao, X-Y. Yang, H-Z. Wang, S.R.E. Hosseini and Y-H. Cheng
The rare earth element, Er, plays a unique role in the formation of the amorphous coating. In this study the effects of different Er element content on the structure, amorphous content, hardness and corrosion resistance of an Fe-based amorphous coating laser clad onto a 1045 low carbon steel base material (BM) were studied. The results showed that the Er element can obviously refine grain, and also increase the amorphous phase content of the cladding layer. With the increase of Er element content, the hardness of the cladded layer was increased gradually and the gradient structure was appeared. At the bottom layer, a thick columnar crystalline structure was created. The middle part was occupied with the crystalline phases having high content of Cr and Mo along with several amorphous phases and equiaxial crystalline structure enriched with Fe. It was also expressed that the corrosion resistance of the cladding layer was optimal value when the mass fraction of Er was 4%.
Keywords: Fibre laser, Er addition, Fe-based, laser cladding, amorphous, hardness, corrosion, structure