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首先在單刃劃切實驗中，發現比切削能的改變不但反映出材料尺寸效應，還有材料移除行為的轉變，而這個隨著切削深度改變的比切削能現象進一步被證實可提供作為估算臨界切削深度之準則。接著在不同切削速度、方式與正向負載等加工參數下，分析延性刮削單晶矽(100)所引起的相變化，應力釋放率此製程特徵值被證實可成功地用於判認矽相的轉變。在應力釋放率小於100 GPa/s時矽材料結構由金屬相Si-II轉變為亞穩定相Si-XII/Si-III，而應力釋放率大於150 GPa/s則導致a-Si的形成。
Understanding the effects of abrasive machining on the material removal mechanism and surface integrity of brittle materials, such as phase transformation and residual stress, can help selection of optimal conditions for ductile-regime machining of brittle material, and give the insights into the formation of phase change and residual stress on machined surface. In this thesis, experiments in scratching and grinding have been conducted to investigate the effect of cutting conditions on surface integrity of single crystalline silicon (100).
In the scratching experiment, it is found that the material size effect in the ductile region as well as the transition in material removal behavior is well reflected by the change in the specific cutting energy. It is shown that the change of specific cutting energy as a function of the cutting depth can serve as a criterion for estimating the critical depth of cut. By analyzing phase changes in the grooves for ductile scratching on single crystals silicon (100) under various cutting conditions, this study shows that stress release rate can serve as a process characteristic value to predict the transition of phase changes. Si-II is shown to transform to the metastable Si-XII/Si-III phase upon a stress release rate smaller than 100 GPa/s whereas the amorphous forms at stress release rate larger than 150 GPa/s.
The silicon grinding processes including groove and surface grinding are carried on the effects of grinding parameters on removal mechanism, phase transformation and residual stress. In the groove grinding experiment, combining the kinematic features of the grinding process and the material fracture criterion, the cutting depth ratio (CDR), defined as the ratio of the maximum uncut chip thickness to the critical depth of cut of brittle materials, is employed to investigate the effects of uncut chip thickness on groove edge chipping and wheel performance. The experiment results indicate that the magnitude of edge chipping, as expected, steadily increase with increasing CDR, and the optimum grinding ratio is shown to occur at unit CDR, where the material removal mechanism is around the ductile/brittle transition region of the silicon. Finally, this thesis studies the effects of chip loads on surface formation mechanism, near-surface residual stress and phase transformation, and their interrelationships in surface grinding of silicon at a fixed wheel speed. It is shown that grinding condition with higher chip load leads to the formation of Si-III/Si-XII phases as well as a higher transverse surface residual stress while a smaller chip load is favorable in the formation of an amorphous phase and low residual stress.