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Ultrasonic Vibration Assisted Cutting of Nomex Honeycomb Core Materials
Dao‑Hui Xiang,Bang‑Fu Wu,Yun‑Long Yao,Bo Zhao,Jin‑Yuan Tang 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.1
Nomex honeycomb core materials have been widely used in the aviation industry due to their special structure and performance. Conventional high-speed machining have resulted in the poor machinability of the honeycomb core so that the ultrasonic machining technology was applied. The kinematic characteristics in the ultrasonic vibration assisted cutting process were analyzed according to the movement of the sharp tool. Based on slide effect, a cutting force model was proposed to study the relationship between cutting parameters and cutting force. Ultrasonic vibration assisted cutting and ordinary cutting tests of Nomex honeycomb core material were conducted by considering feed rate, the inclined angle and the deflected angle. Besides, the effects of cutting parameters on machined surface quality of honeycomb core wall were studied. The test results show that slide effect caused by ultrasonic vibrations can reduce cutting resistance compared with ordinary cutting. The developed cutting force model can be applied to evaluated the cutting force in the ultrasonic vibration assisted cutting of Nomex honeycomb core material. The inclined angle has a great influence on the cutting force during ultrasonic vibration assisted cutting. High-speed reciprocating sliding action can effectively cut aramid fibers so that burrs and tearing defects of the incision have been greatly improved under condition of ultrasonic vibration assisted cutting.
Dao-Hui Xiang,Zhi-Meng Zhang,Bang-Fu Wu,Hao-Ren Feng,Zhan-Li Shi,Bo Zhao 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.11
Silicon carbide particle-reinforced aluminum matrix composite has been widely used in the military and aerospace industry due to its special performance; however, there remain many problems in processing. The present paper introduces an ultrasonic vibration tensile device with a view to investigating an ultrasonic vibration tensile specimen. The results show that there are three major stages in the change in stress of the material under ultrasonic vibration: the ultrasonic stress superposition effect, softening effect, and Hall–Petch strengthening effect, these three effects occupy different proportions in different tensile stages. In addition, increasing the frequency of ultrasonic vibration increased the degree of stress reduction. Increasing the ultrasonic vibration amplitude reduced the fracture strength of the material. Comparison of the fracture morphology shows that the conventional condition was mainly interfacial peeling of SiC particles, and cleavage of the fracture occurred under ultrasonic vibration conditions.
Zhan-Li Shi,Dao-Hui Xiang,Hao-Ren Feng,Bang-Fu Wu,Zhi-Meng Zhang,Guo-Fu Gao,Bo Zhao 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.10
SiCp/Al composites have been widely used in many fields due to their excellent mechanical properties. However, the addition of reinforced phase SiC particles makes the overall properties of the composites hard and brittle, which brings great challenges to milling. Ultrasonic vibration-assisted processing technology has great advantages in processing hard and brittle materials. However, the process of rupture of SiC particles cannot be effectively observed during the test processing, and a large number of tests increase the cost of the test. The combination of finite element analysis and experiment was used to study the machining performance of High-volume fraction SiCp/Al composites in longitudinal-torsional ultrasonicassisted milling (LTUAM), and its feasibility was evaluated by comparing with conventional Milling (CM). By analyzing the trajectories of cutting edges in ultrasonic-assisted milling, It was found that ultrasonic frequency determines the time of periodic contact-separation between chisel edge and workpiece, and ultrasonic amplitude determines the maximum distance of contact-separation. Using ABAQUS finite element software, a polygon SiC particles model with a high-volume fraction was established to investigate the SiC particles crushing process under different ultrasonic-assisted milling conditions. The results showed that high-frequency ultrasonic-assisted milling could soften SiCp/Al composites, and the structural integrity of silicon carbide particles could be better maintained under appropriate ultrasonic amplitudes, reducing the probability of fragmentation. The removal mode was mainly plastic removal or crushing into small particles. The surface roughness value and milling force were reduced, improving the surface quality of the processed composite material. The conclusions of the milling test were basically consistent with the simulation results, which prove the correctness and feasibility of the simulation results