The Study On Organization Structure And Process Performance On Coatings Of Mould Copper Plate

Crystallizer is a core component known as the "heart" of the continuous casting equipment during the continuous casting slab. The cost of continuous casting and rolling can be shortened by increasing the service life of the crystallizer.The influence of processing parameters on micro-hardness in the electrodeposited Ni-Co coatings were investigated by using single variable method, optimization technical conditions was found, and Ni-36.97%Co alloy coating with high hardness, good combination was prepared on the surface of Cu-Cr-Zr. The influence of annealing temperature on micro-hardness and structure of Ni-36.97 %Co coatings were studied and analyzed, and the results showed that the micro-hardness increased firstly and then decreased with the increase of the annealing temperature, and reached 506.2 HV0.05 at 300℃. Showing a strong(111) texture significantly after annealing. The CoO hard phase emerged in the coating through XRD phases analysis.The influence of processing parameters, Fe content and annealing temperature on the Ni-Co-Fe alloy coating were studiedto obtain the optimum processing parameters through adding Fe element into the Ni-36.97 %Co alloy coating. The results showed that the micro-hardness increased first then decreased and reached the highest value at 350℃, existed significant annealing strengthening phenomenon. The grain size of Ni-Co-Fe alloy coatings increased slowly firstly, then increased quickly and the grain size reached micron level before 350℃. Diffraction peak(111) and(200) sharpened constantly with the heat treatment temperature increased, and the(111) plane texture preferred the greater extent of orientation. After the heat treatment of the coatings, phase analysis were carried out by using XRD, the results showed that precipitates precipitated from Ni-Co-Fe alloy coatings and gathered mainly among the(111) and(200) crystallographic plane in the diffraction pattern. The hard phase precipitated from coating increased the hardness. Strengthening mechanism of state-plated Ni-Co-Fe alloy coatings was that due to hard phases FeNi3, Co3 Fe, the hardness increased. The study found electro-deposition time did not change the preferred orientation(111) of Ni-Co-Fe alloy coatings, but the grain size decreased slightly with the increase of electro-deposition time.