Papers by Keyword: Rotary Ultrasonic Machining

Abstract: Poly-crystalline cubic boron nitride (PCBN) is one of the hardest known material. Therefore only advanced methods are able to treat such material. Advanced machining methods, proper for machining of hard and brittle materials (such as glass and ceramics) include rotary ultrasonic machining (RUM). However, high hardness of workpiece cause higher loads and it could negatively affect achievable accuracy and surface topography. Machine loads are affected by both: machined material and machining parameters. This contribution investigates influence of machining parameters, such as spindle speed, feed rate and depth of cut, on loads of machine tool during machining of PCBN by rotary ultrasonic machining.

Abstract: Poly-crystalline cubic boron nitride (PCBN) is one of the hardest known material. Therefore only advanced methods are able to treat such material. Advanced machining methods, proper for machining of hard and brittle materials (such as glass and ceramics) include rotary ultrasonic machining (RUM). This method should achieve high precision and low surface roughness (at least during machining of materials such as ceramics). Achievable roughness is affected by machined material and machining parameters. This contribution investigates influence of machining parameters, such as cutting speed and feed rate, on resultant surface roughness during machining of PCBN by rotary ultrasonic machining.

Abstract: Sapphire, widely used in high-speed integrated-circuit chips, thin-film substrates, and various electronic components, is regarded as one of the most difficult to cut materials owing to its great hardness and low fracture toughness. Rotary ultrasonic machining (RUM) has been regarded as an effective processing method for hard and brittle materials. In this paper, RUM process is introduced into the drilling of sapphire for the first time. The feasibility to machine sapphire using RUM is studied. Moreover, results of a designed experimental study into RUM of sapphire are presented to discuss the main effects as well as interaction effects of process parameters (ultrasonic power, spindle speed, and feedrate) on outputs. The process outputs investigated include cutting force and edge chipping size.

Abstract: The performances of particle reinforced aluminum matrix composite is excellent, but it is hard to be manufactured, which resist its wide spread engineering application. Rotary ultrasonic machining (RUM) is very suit for machining of particle reinforced aluminum matrix composite with moderate or high volume fraction. An aluminum matrix composite reinforced with 45% volume fraction of 3μm silicon carbide particles in a A12 aluminium matrix is experimental studied by RUM, and surface topography, surface roughness and cutting force are analyzed. The experimental results show that machining surface quality is high, surface roughness Ra ranges from 0.131~0.340μm, the cutting process is very smooth and cutting force Fz ranges from 23.33~51.31N, grinding wheel jams and grinding burn do not appear on rotary ultrasonic cutting tool after machining, and tool wear is extremely little.

Abstract: Rotary ultrasonic machining (RUM) is widely used for machining virous kinds of hard-brittle materials. This article aims to study ultrasonic machining surface quality of zirconia ceramic, low-carbonsteel boltwith self-developed rotary ultrasonic machine. The surface roughness could be detected and observed by Taylor Hobson surface roughness instrument and Keyence microscope.The experimental resultsshow that the surface quality achieved by rotary ultrasonic machining is better than bytraditional mechanical machining. Rotary ultrasonic machininghas advantages for machining hard-brittle materials.

Abstract: In this Research, Taguchi optimization methodology is used to optimize Rotary Ultrasonic Machining (RUM) parameters for face milling of zirconia ceramic. The influence of the RUM parameters such as vibration frequency, vibration amplitude, spindle speed, feed rate, and depth of cut on cutting force and material removal rate (MRR) is studied. A three-level orthogonal array table is used to determine the signal-to-noise (S/N) ratios based on Taguchis design of experiments. Furthermore, analysis of variance (ANOVA) has been performed to study the relative significance of the different factors on cutting force and MRR of zirconia ceramic. Finally, verification tests were carried out to compare the predicted values of the outputs with their experimental values in order to confirm the effectiveness of the Taguchi Optimization.

Abstract: SiCp/Al thin-walled structure is processed by rotary ultrasonic machining (RUM). Machining allowance of thin-walled structure is large, manufacturability is bad, and it is vulnerable to vibration to reduce processing quality in machining. Based on analysis of chatter mechanism of RUM, a dynamic model for chatter analyzing and a stability judgment criterion are established and the simulation is conducted for a typical thin-walled component of SiCp/Al composite with time domain analysis method. The simulation results show that machining parameters of RUM could be optimized selected with this model, chatter could be prevented effectively and a good processing effect achieved.

Abstract: Submitted article deals with the impact of the cutting fluid´s pressure on the deviation from circularity. In submitted article an experiment is described when the pressure was changing from 15 to 25 bar in drilling of Al2O3 with ultrasound among other variables, feed and rotational speed. The aim of experiments was to define how the value of circularity of the hole is changing in different depths of machined hole. There is a dependence in USM process where the hole´s perimeter is rising with the depth of hole, however there was no knowledge in this problematics in RUM process. According to results from experiments it can be concluded, that the deviation from circularity is rising with the depth of a hole. The parameter influencing the deviation the most is cutting fluid´s pressure as was expected.

Abstract: Rotary ultrasonic machining(RUM) as a precise and efficient processing method for hard and brittle materials can be used for significantly improving processing efficiency, reducing the cutting force and cutting heat, improving the surface quality. Development of high performance RUM machine tools and equipments has been caused on widespread attention from the worldwide scholars. In this paper, the development of the RUM machine tools has been reviewed about the accessory RUM head and load matching system.

Abstract: Particle reinforced aluminium matrix composites could be used in manufacturing of aviation thin-walled workpiece due to its excellent performances, but it is hard to be manufactured. Rotary ultrasonic machining (RUM) is very suitable for machining particle reinforced aluminum matrix composites with moderate or high volume fraction. Chatter appears very easily in machining process of thin-walled workpiece and it can seriously reduce the quality of components. Based on the dynamic characteristics of machining process, a stability analytical model is built. It is analyzed that the process stability of a thin-walled workpiece of SiCp/Al composites reinforced with 45% volume fraction, and the stability lobe diagram is plotted by using MATLAB. According to stability analysis results, a machining experiment is conducted and the test results indicate chatter could be prevented effectively by this method.