Predicting Multi-Scale Dimensional Accuracy of Engine Cylinder by Honing

The deviations of cylinder bore dimensional accuracy have tremendous influence on engine performances including friction power loss, vibration, leak tightness between piston ring and cylinder wall, and abrasive resistance. Many researches were devoted to capturing cylinder dimensional accuracies by honing using analytical, experimental and simulation methods. These researches investigated the topography and roughness of the honed surface, the relationship between the process parameters and the dimensional accuracies. However, most researches focused on macro-scale dimensional accuracy and micro-scale surface texture respectively. To overcome the limitation, a multi-scale model for cylinder bore honing is proposed to predict the dimensional accuracy and surface texture of cylinder bore at macro-scale and micro-scale simultaneously. The model integrates the microscale factors of the honing stone abrasives distribution characteristics, abrasive wear process, previous cylinder surface topography, and macro-scale factors of cylinder geometry and honing head motion trajectory. A Force matching method is adopted to determine the feed depth of cylinder honing process. Thus the model can predict the roundness, cylindricity, roughness and Abbott-Firestone curve of the honed cylinder bore at multi-scale levels. Simulation results show that material removal distribution is closely related to cylinder bore initial shape deviations. The deviations with long wavelengths cannot be eliminated by the sequential honing.