Northeast Electric Power University Investigation On Surface Coating And Properties Of Mould Copper Plate Prepared By Laser

Mould coper plate is the important part of mould,which has a direct influence on the quality,performance and life of slab in contenuous casting.In this study,chrome-zirconium copper was selected as the experiment material of the mold copper plate,and laser cladding coating with high hardness and wear resistance was prepared by laser cladding technology.the single-layer cladding layer in the first scheme was prepared by Ni60+2%WC power,Ni60+5%WC power,Ni60+10%WC power,respectively.and the composite cladding layer in the second scheme was prepared by Ni45+20%Co42+5%ZrO2 power,Ni45+2%ZrO2/Co42 power,Ni45+5%ZrO2/Co42 power,Ni45+10%ZrO2/Co42 power,respectively.By means of friction and wear test,vickers hardness test,X-ray diffractometer(XRD),scanning electron microscope(SEM)and energy spectrometer(EDS),the friction and wear characteristics and hardness characteristics of cladding layer were studied by two experimental schemes.It provides technical guidance for improving the life of continuous casting mould copper plate and has certain innovation and the application value of engineering.The main research results of this paper are as follows:Through the study and analysis of single-layer cladding layer,it can be seen that the junction of matrix and cladding layer is mainly formed by cellular crystals.It is not difficult to find that the hardness values in sample 1 to sample 4 have different degrees of improvement,compared with the copper matrix.Among them,the hardness value of sample 4 increased the most than that of copper matrix,mainly because the hardness of cladding layer increased with the increase of tungsten carbide content.The Ni60+WC cladding layer is mainly composed of the phases of the y-Ni solid solution,Cr7C3,Cr0.19Fe0.7Ni0.11,Cr23C6 and WC.The Ni60+WC cladding layer can not only increase the friction resistance of copper matrix,and reduce the wear width and wear volume of the cladding layer than that of copper matrix under the same conditions by the laser cladding.It can be seen that the cladding layer can effectively improve the wear resistance of copper matrix.In addition,through the study and analysis of the composite cladding layer,it can be seen that the cobalt-based cladding layer and the nickel-based cladding layer are respectively formed by dendritic crystal,thin-flake crystal and point-like crystal.The hardness of the cladding layer of the sample is higher than that of the copper matrix,and the hardness value of sample 3 increases most than that of the copper matrix.The main phases of the cladding layer are composed of CrSi2,Ni-Cr-Co-Mo,CoO,{Si,Al}2Cr and CoGa3Zr2.Under the same experimental conditions,the wear trace width and wear volume of the cladding layer are reduced and compared with the copper matrix,which indicates that the wear resistance of the cladding layer is improved to the copper matrix.