Abstract
In this study, a Ni–Co composite coating was fabricated successively on a copper substrate by laser, and the microstructure and properties of the composite coating were studied. Our results show that the elements from Ni and Co alloy powder were uniformly distributed in the binding region, which obtained a good metallurgical bonding with the substrate. The microhardness of Co-based coatings was 646 HV0.1, which was approximately 7.6 times greater than the hardness of Cu substrate. The Ni-based coating hardness was a little lower than that of the Co-based coating, which was approximately 7.0 times higher than the hardness of Cu substrate. The Co-based coating was comprised of reinforced phases, such as Co, Ni–Cr–Co–Mo, M7C3 and {Fe, Ni}. The wear volume of Co-based coatings was approximately 0.164 mm3 after the sliding wear test at 60 min, which was only 4% of the substrate’s wear volume. Meanwhile, the heat shock resistance experiment was carried out at 800 °C for 75 times before the Ni–Co composite coating was peeled off. It was shown that this Ni–Co composite coating had good wear resistance and high temperature properties, which is helpful to improve the service life of a mould copper plate. It not only saves the economic cost of steel plants, but also improves the quality of slabs and products.
Highlights
It is well known that mould is the key component of continuous casting, so it is usually called the “heart” of the continuous casting machine
If the Cu element produced by the wear and friction enters into liquid steel, a large number of surface cracks will appear and the quality of the slab declines, which greatly limits the application of a mould copper plate [2]
These poresofin coating decrease the service life ofimpurities, a mould copper. It pores in the coating decrease the service life of a mould copper plate
Summary
It is well known that mould is the key component of continuous casting, so it is usually called the “heart” of the continuous casting machine. The wear resistance of a mould copper plate needs to be improved, which is helpful to prolong its service life and produce slab products of high quality. Some surface treatments, such as electroplating and thermal spraying, can be used to improve wear resistance of mould copper plates [3,4,5]. Zhao et al.fabricated [16] prepared stainless steel transition copper substrates electroplating technology, and a Co acoating with laser. Steel transition on copper substratesalloy by friction stirwas welding, a Ni-based alloy coating prepared a laser cladding coating of.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
