1Modeling and experimental analysis of microburr formation considering tool edge radius and tool-tip breakage in microend milling

摘要

The microburr formation in the microend milling of aluminum alloy A12024-T6 using tungsten-carbide cutter is investigated in this article. The three-dimensional finite element model is developed to analyze microburr formation in microend-milling process. This model predicts the effects of various tool edge radiuses and tool-tip breakage on the burr formation. The microburr formation is dynamically simulated. The simulation results show that there are three basic types of burrs (entrance burr, top burr, and exit burr) along the feature edges. The burrs formed in microend milling are larger than those formed in conventional milling in certain range. The effect curve of tool edge radius on the top-burr height is obtained. Various tool edge radii are found to have significant influence on the top-burr formation. The salient size effect of microburr morphologies is observed in the experiment and simulation. Experimental verification of the simulation model is carried out in the process of microend milling of aluminum alloy A12024-T6. The simulation for influence of various tool edge radii (new tool and worn tool) and tool-tip breakage on the exit-burr height has been verified in experiments. Top-burr heights in simulation and experiments have maximum error about 10%. The experimental results also show that the model is suitable for predicting the morphologies and dimensions of microburrs.