Research On The Properties Of Laser Cladding 316L/BN Composite Coatings

What has plagued us is the corrosion of metal materials,which has always been a major problem.With the further development of laser technology,laser cladding technology has also been rapid development.It can coat a corrosion-resistant alloy coating on the metal surface,that will effectively improve the corrosion resistance of metal materials.Furthermore,the powder cladding system in laser cladding also progresses from a single alloy powder to a composite powder,which will also allow for a broader and broader space for coating research in the future.With the deep exploration of marine resources,the research on corrosion resistance of metals has become even more prominent.In this context,the high-power semiconductor laser has used to laser-clad the 316 L and 316L/BN composite powders on the surface of 45# steel.Then based on theoretical knowledge,the paper has studied the macroscopic morphology,phase composition and microscopic properties,tissue structure,microhardness,wear resistance and seawater corrosion resistance.of the cladding coatings.Firstly,combined with metal solidification theory,the crystal morphology of laser cladding molten pool has studied,which has provided a theoretical reference for the microstructure in the experiment.Then,the defects of the cladding process have studied to avoid the occurrence of thermal cracks in the cladding test.In view of the corrosion of metals in seawater,a method for assessing the degree of metal corrosion has derived and the formula for calculating the corrosion rate of metals has deduced.Because of Laser cladding technology is a complex physical chemistry process,there are many factors affecting the forming quality and internal structure of the cladding surface.Therefore,under the single factor test,the paper has discussed for that different laser process parameters have effect on macroscopic morphology,microstructure,and microhardness of a single lane of 316 L cladding layer.As well as laser power and scanning speed take effect on the quality and overall performance of the coating surface.They provide the basis on the process parameters for multiple 316 L and 316L/BN composite coatings.Finally,based on the powder design principle,316L/BN composite powders with different BN content ratios ranging from 0% to 12.5% have been designed.Compared with macroscopic morphology,XRD phase analysis,microstructure,EDS energy spectrum analysis,micro-hardness,wear resistance test,and corrosion resistance test,the macroscopic morphology,microstructure,micro-hardness,wear resistance,and corrosion resistance of the coating,and summarizing the changing rules of various aspects of the composite coating due to different contents of BN.The improved effect of 316 L stainless steel cladding layer provides a certain reference value for further research and production practice in the future.