Research On Meso Scale Machining Error Propagation And Accuracy Control

Definition of meso scale is that the size of parts is in the range of0.1~10mm, and thesize of characteristics is in the range of0.01~1mm, which is between micro scale andmacro scale. In recent years, with the development of the miniaturization of products,application of meso scale components in biomedicine, information communication,aerospace, military and other fields of high-tech electronic products are more and morewidely. Micro cutting is capable for manufacturing3D features, such as deep hole, deepgroove, free surface, and it has little limit with the materials of work piece. Thus, manyscholars of various countries have turned to the field of micro cutting, making the microcutting technology has become a research hotspot in recent years.Because of several reasons, such as the small size of part and tiny feed rate, themachining mechanism of meso scale milling is different with that in macro scale. Suchsituation, named size effects, has a great influence on machining accuracy. In addition,meso scale part has many structures, and high requirement of accuracy. A lot of errorsources affect the machining precision during multistage machining. All of these result indifficulties of accuracy control.To deal with this problem, series of researches have done in this paper:(1) Based on the manufacturing process, through the analysis of possible problems in partdesigning and manufacturing process, established a machining accuracy control systemincluding dimensional variation model, multivariate statistical process control anddiagnosability analysis of error source was put forward to provide basis of multi-stagedigital manufacturing of meso scale part.(2) Meso scale part has complex structures. Analyzed the manufacturing error source insingle stage, and error transfer between stages. Considering of the size effects in mesoscale cutting, the deviation state space model of datum, re-located and fixture errors,especially machining errors including the influences of work piece’s and tools’deflection was proposed.(3) Based on the analysis of characteristics of meso scale parts and its characteristics in theprocess of cutting, studied the method of calculating the actual instantaneous cuttingthickness of each tooth milling process, considering the influence of minimum cuttingthickness, cutting edge radius and other micro cutting scale effect and the spindle run-out on the cutting force. And established a force prediction model for the mesoscale milling process.(4) Groove milling experiments have conducted in310S stainless steel to validate themodels proposed in chapter2to4. At the same time, according to the test results,analyzed the influence of cutting parameters on meso scale milling force.All of the researches in this paper supports for the implementation of the meso scalemilling process optimization.