工程材料切削加工性与核磁兼容性研究-机械工程专业论文.docxVIP

ABSTRACT Operation accuracy, equipment life, the magnetic resonance (MR) image quality , safety of the patients and the surgical devices will be influenced by the materials that are used to manufacture the magnetic resonance imaging (MRI) guided robot. This paper focuses on the evaluation theory of material machinability, mechanistic force modeling and MR safety and compatibility based on the MRI-guided surgical robot. Theoretical analysis is completed and experiments are designed to validate the precision of the theory. The main work and the gained results are summarized into three aspects and listed below: Firstly, due to the importance of material machinability to the MRI-guided robot, the methods that can be applied to evaluate machinability are introduced and the theoretical formula is established based on the previous study. Milling experiments are done to test the quantitative value of the factors that are used to evaluate machinability in the theoretical system. Based on the theoretical and experimental results, the ranks of the candidate materials’ machinability are obtained. Polyformaldehyde is the best. Secondly, the mechanism of milling process is analyzed. The variation of uncut chip, the shear mechanism of the rake face, the rubbing and ploughing effects of the rank flutes combined with the cut mechanism of the chisel edge are studied. The mechanistic force model is acquired synthesizing the previous analysis. Milling experiments are conducted to validate the model and it is found that the deviation is below 10%. Finally, MR safety and compatibility of materials are analyzed in three aspects: theory, simulation and experiment. The interaction between material and the magnetic field is studied and typical factors that impose on MR compatibility are studied. Simulations are dependent on theoretical results and then extended to a broader scope to test the factors that influence MR compatibility. Based on theoretical and simulation results, experiments ar