scholarly journals Experimental Investigation on Micro-Groove Manufacturing of Ti-6Al-4V Alloy by Using Ultrasonic Elliptical Vibration Assisted Cutting

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3086 ◽  
Author(s):  
Rongkai Tan ◽  
Xuesen Zhao ◽  
Tao Sun ◽  
Xicong Zou ◽  
Zhenjiang Hu
Keyword(s):  
High Precision ◽  
Surface Integrity ◽  
Cutting Speed ◽  
Groove Depth ◽  
Experimental Results ◽  
High Quality ◽  
Elliptical Vibration ◽  
Lubrication Performance ◽  
Material Swelling ◽  
Ultrasonic Elliptical Vibration

The micro-groove structure on the planar surface has been widely used in the tribology field for improving the lubrication performance, thereby reducing the friction coefficient and wear. However, in the conventional cutting (CC) process, the high-quality, high-precision machining of the micro-groove on titanium alloy has always been a challenge, because considerable problems including poor surface integrity and a high level of the material swelling and springback remain unresolved. In this study, the ultrasonic elliptical vibration assisted cutting (UEVC) technology was employed, which aimed to minimize the level of the material swelling and springback and improve the machining quality. A series of comparative investigations on the surface defect, surface roughness, and material swelling and springback under the CC and UEVC processes were performed. The experimental results certified that the material swelling and springback significantly reduced and the surface integrity obviously improved in the UEVC process in comparison to that in the CC process. Furthermore, for all the predetermined depths of the cut, when the TSR (the ratio of the nominal cutting speed to the peak horizontal vibration speed) was equal to one of twenty four or one of forty eight, the accuracy of the machined micro-groove depth, width and the profile radius reached satisfactorily to 98%, and the roughness values were approximately 0.1 μm. The experimental results demonstrate that the UEVC technology is a feasible method for the high-quality and high-precision processing of the micro-groove on Ti-6Al-4V alloy.

Development and optimization of ultrasonic elliptical vibration cutting device based on single excitation

2021 ◽  
pp. 1-29
Author(s):  
Sen Yin ◽  
Zhigang Dong ◽  
Yan Bao ◽  
Renke Kang ◽  
Wenhao Du ◽  
...  
Keyword(s):  
Cutting Speed ◽  
Tungsten Alloy ◽  
Asymmetric Structure ◽  
Diamond Cutting ◽  
Elliptical Vibration Cutting ◽  
Vibration Cutting ◽  
Elliptical Vibration ◽  
Technical Capability ◽  
Diamond Cutting Tool ◽  
Ultrasonic Elliptical Vibration

Abstract Ultrasonic elliptical vibration cutting (UEVC) technique, as an advanced cutting method, has been successfully applied to machine difficult-to-cut materials for the last decade. In this study, the mechanism of the elliptical vibration locus caused by the “asymmetric structure” of the horn was analyzed theoretically firstly, and the corresponding relationship between the degree of asymmetry and the elliptical vibration locus was determined based on finite element method (FEM). Then an efficient single-excitation UEVC device with “asymmetric structure” was developed and optimized. The resonant frequency of the device was 40.8 kHz, and the amplitude reached 12.4 µm, which effectively broke the limitation of cutting speed in UEVC. Finally, the UEVC device's performance was tested, and the advantages in improving the tungsten alloy surface quality and reducing diamond cutting tool wear validated the technical capability and principle of the proposed device.

Modeling of the Effect of Machining Parameters on Maximum Thickness of Cut in Ultrasonic Elliptical Vibration Cutting

2011 ◽  
Vol 133 (1) ◽  
Author(s):  
Chandra Nath ◽  
Mustafizur Rahman ◽  
Ken Soon Neo
Keyword(s):  
Brittle Materials ◽  
Cutting Speed ◽  
Role Playing ◽  
Machining Parameters ◽  
Elliptical Vibration Cutting ◽  
Tool Vibration ◽  
Vibration Cutting ◽  
Elliptical Vibration ◽  
Hard And Brittle Materials ◽  
Ultrasonic Elliptical Vibration

In recent years, the ultrasonic elliptical vibration cutting (UEVC) technique has been found to be an efficient method for the ultraprecision machining of hard and brittle materials. During the machining at a given nominal depth of cut (DOC), the UEVC technique, because of its inherent mechanism, effectively reduces the thickness of cut (TOC) of the workpiece material through overlapping vibration cycles. For the ductile machining of hard and brittle materials, this TOC plays a critical role. However, the relationships between the nominal DOC, the TOC, and the relevant machining parameters have not yet been studied. In this study, the role playing machining parameters for the TOC are firstly investigated and then theoretical relations are developed for predicting the maximum TOC (TOCm) with respect to the relevant machining parameters. It is found that four machining parameters, namely, workpiece cutting speed, tool vibration frequency, and tangential and thrust directional vibration amplitudes, influence the TOCm. If the speed ratio (ratio of the workpiece cutting speed to the maximum tool vibration speed in the tangential direction) is within a critical value 0.12837, then a reduced TOCm can be obtained. It is also realized that if the TOCm can be kept lower than the critical DOC (DOCcr), then ductile finishing of brittle materials can be achieved. The above phenomenon has been substantiated by experimental findings while machining a hard and brittle material, sintered tungsten carbide. The findings suggest that the same concept can be applied for the ductile cutting of other hard and brittle materials.

Drilling Assisted by Ultrasonic Elliptical Vibration

2005 ◽  
Vol 291-292 ◽  
pp. 443-446 ◽  
Author(s):  
Chun Xiang Ma ◽  
Eiji Shamoto ◽  
T. Moriwaki
Keyword(s):  
Chip Thickness ◽  
Experimental Results ◽  
Drilling Process ◽  
Drilling Force ◽  
Elliptical Vibration ◽  
Drilling System ◽  
Radial Drilling ◽  
Ultrasonic Elliptical Vibration

The drilling assisted by ultrasonic elliptical vibration (UEV) is proposed in present paper. The drilling system assisted by UEV was developed. The characteristics of the drilling process assisted by UEV are analyzed. The effect of ultrasonic elliptical vibration on the axial drilling force, the radial drilling force and the chip thickness are investigated experimentally. The experimental results show that the axial drilling force, the variation of the radial drilling force and the chip thickness of drilling assisted by UEV can be reduced.

Micro Hole Elliptical Supersonic Boring Quality Research

2012 ◽  
Vol 217-219 ◽  
pp. 1688-1694
Author(s):  
Ji Liang Wu ◽  
De Yuan Zhang ◽  
Xing Gang Jiang
Keyword(s):  
Cutting Force ◽  
High Quality ◽  
Elliptical Vibration Cutting ◽  
Quality Research ◽  
Vibration Cutting ◽  
Elliptical Vibration ◽  
Longitudinal Excitation ◽  
Micro Hole ◽  
Ultrasonic Elliptical Vibration ◽  
Quality Surface

In this paper a method of ultrasonic elliptical vibration cutting has been applied to precision boring of micro hole due to its superior performances such as low cutting force, high quality surface finish and long tool life. A transducer with the longitudinal excitation is carried out to machining(boring) micro hole of 1Cr18Ni9Ti workpiece. The cutting force and surface quality are studied in detail.The workpiece with surface roughness of Rz 0.4μm is achieved.The results showed that the ultrasonic elliptical vibration transducer can be applied rationally in micro hole precision boring.

scholarly journals Investigation on the Cutting Mechanism of Al/SiCp Composites in Ultrasonic Elliptical Vibration Machining

2021 ◽  
Author(s):  
Wenxiang Chen ◽  
Xu Zhang
Keyword(s):  
Stress Distribution ◽  
Cutting Force ◽  
Surface Integrity ◽  
Machining Process ◽  
Von Mises Stress ◽  
Cutting Mechanism ◽  
Machined Surface ◽  
Elliptical Vibration ◽  
Von Mises ◽  
Ultrasonic Elliptical Vibration

Abstract Aluminum (Al)-based silicon carbide (SiC) material composites are considered as difficult-to-machine materials because of the presence of hard reinforced SiC particles, which results in a greater cutting force and poor surface integrity during the machining process. This paper uses two finite element models to study the difference in the machining mechanism between ultrasonic elliptical vibration cutting (UEVC) and ordinary cutting (OC). Moreover, this paper mainly focuses on the influence of UEVC on cutting force, von Mises stress distribution, surface integrity, and chip formation. The models are validated by comparing chip shapes and machined surface features in OC machining Al/SiCp experience from the literature. Simulation results indicate that the cutting mechanism of Al/SiCp on UEVC is different from that of OC and has several good properties. At the same cutting parameters, high frequency vibration makes the cutting force of UEVC exhibit variable periodicity and reduces average cutting force. The instantaneous impact of tool and fast separation results in a more concentrated von Mises stress distribution, thereby resulting in the particles having a greater break degree than that obtained with OC. A comparison of the surface roughness values from the simulation result shows that UEVC obtains better surface integrity than OC does.

Study on the Cutting Force in Ultrasonic Elliptical Vibration Cutting of Hardened Stainless Steel

2011 ◽  
Vol 55-57 ◽  
pp. 327-331 ◽  
Author(s):  
Cheng Mao Zhang ◽  
Cheng Li ◽  
De Yuan Zhang
Keyword(s):  
Cutting Force ◽  
Stainless Steels ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Elliptical Vibration Cutting ◽  
Vibration Cutting ◽  
Elliptical Vibration ◽  
Feed Force ◽  
Cemented Carbide Tools ◽  
Ultrasonic Elliptical Vibration

Hardened stainless steels are materials widely used in the field of aviation and spaceflight. Machining of this materials with conventional cutting (CC) method is a real challenge compared to other difficult-to-cut materials. Ultrasonic elliptical vibration cutting (UEVC) method is a novel and non-conventional cutting technique which has been successfully applied to machine such intractable materials for the last decade. However, few studies have been conducted on the cutting force in ultrasonic elliptical vibration cutting of hardened materials. This paper presents an experimental study on cutting force in UEVC of hardened stainless steels using cemented carbide tools. Experiments have been carried out to investigate the effect of cutting parameters in the UEVC method in terms of cutting force, while cutting hardened stainless steels. The tests have revealed that the average thrust force,principal force and feed force drop to 3%,10% and 90% of CC value for UEVC of hardened stainless steels. The ratio between the CC force and the UEVC force decrease with the increase of DOC and cutting speed.

Detecting “DeepFakes” in H.264 Video Data Using Compression Ghost Artifacts

2020 ◽  
Vol 2020 (4) ◽  
pp. 116-1-116-7
Author(s):  
Raphael Antonius Frick ◽  
Sascha Zmudzinski ◽  
Martin Steinebach
Keyword(s):  
Image Forensics ◽  
Video Data ◽  
Experimental Results ◽  
Video Sequences ◽  
The Internet ◽  
Video Content ◽  
High Quality ◽  
The Public

In recent years, the number of forged videos circulating on the Internet has immensely increased. Software and services to create such forgeries have become more and more accessible to the public. In this regard, the risk of malicious use of forged videos has risen. This work proposes an approach based on the Ghost effect knwon from image forensics for detecting forgeries in videos that can replace faces in video sequences or change the mimic of a face. The experimental results show that the proposed approach is able to identify forgery in high-quality encoded video content.

UKP-laserbasierte Herstellung von Netzen unterschiedlicher Transmissionsgrade/USP-laser based production of meshes of different transmission degrees

2020 ◽  
Vol 110 (11-12) ◽  
pp. 787-789
Author(s):  
Marcel Simons ◽  
Till Rusche ◽  
Tobias Valentino ◽  
Tim Radel ◽  
Frank Vollertsen
Keyword(s):  
High Precision ◽  
Processing Speed ◽  
Laser Processing ◽  
Short Pulse ◽  
High Quality ◽  
Mesh Width ◽  
Variable Transmission ◽  
Ultra Short Pulse ◽  
Mesh Structures

Die Ultrakurzpuls (UKP)-laserbasierte Bearbeitung erlaubt die Herstellung von Netzstrukturen mit verschiedenen Transmissionsgraden. Vorteile der UKP-laserbasierten Herstellung der Netze liegen vor allem in der hohen Präzision und Bearbeitungsgeschwindigkeit. Die UKP-Laserbearbeitung ermöglicht die Herstellung von Netzen aus Aluminium in hoher Qualität, bezogen auf die Stegbreitenabweichung von < 8 µm, mit variablen Transmissionsgraden. Ultra-short pulse (USP) laser based processing enables the production of mesh structures with different degrees of transmission. The advantages of USP-based production of mesh structures are mainly the high precision and processing speed. USP laser processing enables the production of meshes of aluminum in high quality, with respect to the mesh width deviation of < 8 µm with variable transmission degrees.

scholarly journals How the Multiplicity of Suggested Information Affects the Behavior of a User in a Recommender System

Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 741
Author(s):  
Yuseok Ban ◽  
Kyungjae Lee
Keyword(s):  
High Precision ◽  
Recommender System ◽  
Visual Information ◽  
Experimental Results ◽  
Supplementary Information ◽  
Digital Platform ◽  
Different Types ◽  
Types Of Information

Many researchers have suggested improving the retention of a user in the digital platform using a recommender system. Recent studies show that there are many potential ways to assist users to find interesting items, other than high-precision rating predictions. In this paper, we study how the diverse types of information suggested to a user can influence their behavior. The types have been divided into visual information, evaluative information, categorial information, and narrational information. Based on our experimental results, we analyze how different types of supplementary information affect the performance of a recommender in terms of encouraging users to click more items or spend more time in the digital platform.

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