The Study Of Edge Deformation Druing Drilling Of SiCp/Al Composites

Because Si Cp/Al composite materials had good physical and mechanical properties, so the people from scientific community have attached great importance to it. But its good performance also brought many difficulties to machining. For example on the edge of workpiece frequently appeared side damage, fracture and edge defects after the machining, these phenomena were edge defects which would reduced its use value in practical application.In this paper, through combining the finite element and experimental analyzed the formation mechanism and influencing factors of edge defects of Si Cp/Al composite materials during the process of drilling. Comparing the experimental results with the experimental results, he paper would expounded the reason why there were differences between the finite element method and experiment method. The specific research work as followed:First of all, using finite element method introduced the formation mechanism of edge defects during the process of drilling, the formation process which didn’t add reinforcing particles was briefly divided into four processes: the phase of shear deformation, stress transmission, distortion and edge effect formation. The following compared finite element simulation results with experimental results, expounded the reason why there were a difference. Through the analysis of the role of tensile stress and compressive stress further understood the formation mechanism of edge defects.The second, using finite element method studied composite materials which were added reinforcing particles in the simulation. The finite element simulation added reinforcing particles could be more close to actual, so drilling process could be divided into five stages: the stages of shear deformation, micro crack initiation, obvious stress transmission, formation of fracture and formation of edge defect. Because in the researching process of edge defect the effect of cutting force couldn’t be lacked, so the cutting parameters must be studied how did it influence on cutting force and the edge defect. Through the study concluded that with the increase of feed speed cutting force and the value of edge defect were both increased. At the same time due to the composite materials added or not added particle composites were studied by using finite element methods, so you need to contrast the difference between them. Comparing the simulation results of the two studies, it concluded that the value of edge defect of composite materials added particle composites was greater than that composite materials not added particle composites. Nest it was studying that how did the volume fraction of reinforcing particles affect the edge defects and the cutting force, through the study concluded that with the increase of volume fraction edge defects and the cutting force both showed a trend of increase.Finally, the number of edge defects and the cutting force were obtained through the experiment. Through the analysis of formation mechanism of export edge defects in the process of cutting drill provided theoretical basis for the following experiment. After that analysising the relationship between the chip and edge defects, showed the similarities and differences between chip morphology and the size of edge defects. At last, through the orthogonal experiment found out the biggest factor that influence the edge defects, and using regression analysis further expounded the results of orthogonal experiment.