Study On The Remanufacturing Of Marine Diesel Engine Cylinder Liner Based On Laser Cladding

The marine diesel engine is used as the ship's power equipment to provide a safe and stable navigation for the ship.As the key components of marine diesel engine,the cylinder liner has extremely harsh working environment,high explosion pressure on the inner surface,high combustion temperature and high and low temperature of cyclic change.In addition,the wear caused by the reciprocating relative motion also affects the life of the cylinder liner.And the electrochemical corrosion and cavitation of the outer surface are also important factors affecting the reliability of the cylinder liner.In recent years,the degree of strengthening of diesel engines has been continuously improved,and the resulting failure forms such as corrosion and cracks have caused cylinder liners to be scrapped in advance without reaching the wear limit,resulting in waste of resources.From a technical point of view,the laser cladding technology can realize the repair of the cylinder liner,realize the reuse of the cylinder liner,and improve the use efficiency.Based on the investigation of the application of laser cladding technology at home and abroad,this study analyzes and studies the use principle of laser cladding technology,compares the characteristics and application advantages of laser cladding technology,and compares common cylinder liners.The failure form was classified.In this study,based on the characteristics of laser cladding particles and the characteristics of the workpiece,it was determined that the Fe-based alloy powder was used for cladding repair on the HT25-47 substrate,and the macroscopic quality and microhardness of the sample and the workpiece before and after repair were fully evaluated.The main research contents are as follows:(1)Investigating the application status of laser cladding technology in the industry,based on the status quo,put forward the feasibility of laser cladding of cylinder liner technology,and analyze its research significance.(2)Classification of the failure modes of the marine diesel engine cylinder liner,the failure modes of the inner wall of the cylinder liner are divided into abrasive wear,abrasive wear,adhesive wear and composite wear,and the outer wall wear of the cylinder liner is mainly cavitation and crack.(3)The effects of key parameters of laser cladding on the cladding structure,such as substrate temperature,laser power and scanning speed,were studied.The experimental results were used to summarize the optimal substrate preheating temperature of 30 ?,power of 2800W,and scanning speed.10mm/s.(4)The cylinder liner was laser-clad with the optimized parameters to realize the repair of the cylinder liner,and finally confirmed that the cladding material and laser cladding process used in this study can achieve higher remanufacturing quality.