Study Of The Cladding Technology By The Protection Of High-temperature Coating

Cladding is widely applied in the industry as a new metal surface treatment technology. Ni-based alloy is a common used cladding material due to its good perfomance, such as wear resistanee, heat resistance and eoorrsion resistanee. But the researcher,s new study is how to develop a high cladding quality and non-dilution cladding.This paper reports on a new cladding method under the protection of high-temperature coating. First, a layer of Stelite Ni60 alloy powder was prepared on the substrate steel and the alloy layer was covered with a layer of high-temperature protective coating. After drying the sample which was heated to the melting point of Ni60 alloy powder in a high-temperature resistance furnace. Then the sample was taken out of the furnace and cooled down. A uniform, adherent and non-dilution clad coating can be obtained after optimizing the cladding parameters.In this paper, at the first, the high-temperature protective coating power and binder was selected. Then, the optimum cladding parameters was determined after a series of experiments. Finally, the cladding morphologies, microstructures, phase structure, element component and the microhardness were observed and analyzed by optical microscope (OM), field emission scanning electron microscope (SEM), X-ray diffraction (XRD), EPMA Scanner and microhardness tester.Experimental results showed that the high-temperature protective coating cladding can prevent the Ni60 alloy powder and matrix from oxidizing and a uniform, adherent and non-dilution cladding layer can be obtained. According to XRD,γ-[Fe,Ni] solid solution, Cr0.19Fe0.7Ni0.11 phase, Cr7C3 and Cr23C6 carbide were formed. At the same time, the interface between the clad coating and matrix belongs to the metallurgical bond with the characteristic of non-dilution. The adverse effects of high temperature on the matrix material can be overcome by means of the normalizing treatment after the high-temperature protective coating cladding. Finally, compared with the induction melting, the high-temperature protective coating cladding has many advantages, such as high cladding quality, low cladding cost, and various shape cladding.