High-speed Laser Cladding Preparation Of Internal And External Surface Coating Process And Performance Research

High-speed laser cladding technology can produce high-performance coatings on the surface of substrates and greatly improve the cladding efficiency,which has unique advantages in the field of metallurgical coating applications.Highspeed laser cladding technology has a linear speed of more than 10m/min,which is more than 5 times higher than traditional laser cladding technology and more than 3 times higher cladding efficiency.In this paper,the key components of the hydraulic support system in the mine,column and cylinder barrel,are studied.The column and cylinder barrel often fail and scrap due to the lack of wear resistance and corrosion resistance,which leads to rusting and peeling on the inner and outer surfaces of the parts.The coating can effectively prolong the service life of hydraulic support,save cost and effectively promote the green production.In this paper,the laser cladding process is simulated using the finite element analysis method,and the cladding process is realized using the "life and death of element" and load of the body temperature rate,and the laser cladding process parameters are clustered.The effect mechanism on the coating was investigated.The results show that the temperature gradient increases with increasing laser output,and the residual stress increases,and the temperature gradient decreases with increasing scanning speed,and the residual stress main stress decreases.The orthogonal test method was adopted to study the mechanism of process parameters affecting the surface quality,microstructure and properties of the coatings under the premise of enhancing the melting and coating line speed.The coatings prepared with different parameters had flat and defect-free surfaces and similar microstructure with slight differences in size,mainly fine columnar dendrites and reticulated equiaxed crystals.The correlation between microhardness and process parameters was investigated by one-way ANOVA,and the microhardness increased with increasing power and powder feeding rate.The reason for the difference in performance is that the change in parameters leads to the difference in the internal microstructure of the coating and the surface quality of the coating.High wear resistance and high corrosion resistance coating was successfully prepared on the inner surface of semi-enclosed space cylinder barrel using high speed laser melting technology,with tiny particles on the inner wall coating surface and no cracks and pit defects.The coating performance was slightly reduced compared with the outer surface coating prepared under the same process parameters because of the difference in the internal organization of the coating due to the poor heat dissipation capability on the inner surface of the cylinder barrel.In addition,during the inner wall fusion coating process,the unmelted powder particles are impacted by the rebound of the inner wall to the incompletely solidified surface coating,the surface quality is reduced and the coating performance is slightly reduced compared to the outer surface coating.