发动机缸孔熔射材料关键缺陷的微观机理及全流程工艺优化

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中图分类号：TG174.4 文献标志码：B DOI：10.19710/J.cnki.1003-8817.20250265

The Microscopic Mechanism of Key Defects and the Optimization of the Entire Process Technology for Spraying Material of Engine Cylinder Bores

LiangXiulan，LiJianping，Zhou Lei，LiLin （Dongfeng Nissan Passenger Vehicle Company，Guangzhou 510800）

Abstract：Tosolve thedefectsof theenginecylinderborethermal spraymaterials，namelythebritlefractureof welding wire，thepeelingof copper plate layer，andthecoating holes，thedefect mechanism isclarified through microstructure analysisandfull-process process optimization，and corresponding countermeasuresare formulated.The results showthatthe britlefractureoftheimported material iscausedbythe large amountof hard bainiteresulting fromcomposition segregation，which causes cracks during drawing.The electromagnetic stirring，light pressure reduction and "air cooling + slow cooling" process can efectively inhibit bainite and avoid britle fracture.The peeling of the copper plating layer is mainly due to insuficient bonding forceand low mold surface finish.The“alkaline preplating + acidic main plating”and diamond coating drawing diecansignificantly improve it.The coating holes are related toprocessfluctuations，nozleslaggingandcleanliness.Throughreal-timemonitoringofkeyparameters，nozzle maintenance and cleanliness system control，the defect rate of holes isreduced byabout 70% .This providesa systematic technical path for thedevelopmentand qualitycontrol of high-performance cylinder bore thermal spray materials.

Keywords：Enginecylinder bore，Thermal spraying，Brittle fracture，Coating holes

1前言

可变压缩比[1-2技术通过引入执行电机与多连杆机构，使发动机压缩比可在一定范围内之间连续调节，从而显著提升燃油经济性与工况适应性。（剩余9879字）