scholarly journals Ultrasound Effect on the Microstructure and Hardness of AlMg3 Alloy under Upsetting

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1010
Author(s):  
Przemysław Snopiński ◽  
Tibor Donič ◽  
Tomasz Tański ◽  
Krzysztof Matus ◽  
Branislav Hadzima ◽  
...  
Keyword(s):  
Flow Stress ◽  
Ultrasonic Vibration ◽  
Light And Electron Microscopy ◽  
Load Flow ◽  
Forming Limit ◽  
Ultrasonic Vibrations ◽  
Softening Effect ◽  
Simultaneous Application ◽  
Ultrasonic Assisted ◽  
Acoustic Softening

To date, numerous investigations have shown the beneficial effect of ultrasonic vibration-assisted forming technology due to its influence on the forming load, flow stress, friction condition reduction and the increase of the metal forming limit. Although the immediate occurring force and mean stress reduction are known phenomena, the underlying effects of ultrasonic-based material softening remain an object of current research. Therefore, in this article, we investigate the effect of upsetting with and without the ultrasonic vibrations (USV) on the evolution of the microstructure, stress relaxation and hardness of the AlMg3 aluminum alloy. To understand the process physics, after the UAC (ultrasonic assisted compression), the microstructures of the samples were analyzed by light and electron microscopy, including the orientation imaging via electron backscatter diffraction. According to the test result, it is found that ultrasonic vibration can reduce flow stress during the ultrasonic-assisted compression (UAC) process for the investigated aluminum–magnesium alloy due to the acoustic softening effect. By comparing the microstructures of samples compressed with and without simultaneous application of ultrasonic vibrations, the enhanced shear banding and grain rotation were found to be responsible for grain refinement enhancement. The coupled action of the ultrasonic vibrations and plastic deformation decreased the grains of AlMg3 alloy from ~270 μm to ~1.52 μm, which has resulted in a hardness enhancement of UAC processed sample to about 117 HV.

scholarly journals Investigation on Microsheet Metal Deformation Behaviors in Ultrasonic-Vibration-Assisted Uniaxial Tension with Aluminum Alloy 5052

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 637 ◽  
Author(s):  
Chunju Wang ◽  
Weiwei Zhang ◽  
Lidong Cheng ◽  
Changqiong Zhu ◽  
Xinwei Wang ◽  
...  
Keyword(s):  
Ultrasonic Vibration ◽  
Thin Sheet ◽  
Acoustic Energy ◽  
Machining Process ◽  
Residual Effects ◽  
Forming Limit ◽  
Uniaxial Tensile ◽  
Softening Effect ◽  
Deformation Ability ◽  
Acoustic Softening

Ultrasonic vibration (UV) is widely used in the forming, joining, machining process, etc. for the acoustic softening effect. For parts with small dimensions, UV with limited output energy is very suitable for the microforming process and has been gaininf more and more attention. In this investigation, UV-assisted uniaxial tensile experiments were carried out utilizing GB 5052 thin sheets of different thicknesses and grain sizes, respectively. The coupling effects of UV and the specimen dimension on the properties of the material were analyzed from the viewpoint of acoustic energy in activating dislocations. A reduction of flow stress was found for the existing acoustic softening effects of UV. Additionally, the residual effects of UV were demonstrated when UV was turned off. The uniform deformation ability of thin sheet could be improved by increasing the hardening exponent with UV. The experimental results indicate that UV is very helpful in improving the forming limit in microsheet forming, e.g., microbulging and deep drawing processes.

Evolution of acoustic softening effect on ultrasonic-assisted micro/meso-compression behavior and microstructure

Ultrasonics ◽  
2020 ◽  
Vol 107 ◽  
pp. 106107
Author(s):  
Jun Hu ◽  
Tetsuhide Shimizu ◽  
Tomoaki Yoshino ◽  
Tomomi Shiratori ◽  
Ming Yang
Keyword(s):  
Softening Effect ◽  
Compression Behavior ◽  
Ultrasonic Assisted ◽  
Acoustic Softening

A method and apparatus for determination of the ultrasonic-assisted forming limit diagram

2021 ◽  
pp. 095440622110115
Author(s):  
Nima Najafizadeh ◽  
Majid Rajabi ◽  
Ramin Hashemi ◽  
Saeid Amini
Keyword(s):  
Material Selection ◽  
Forming Limit Diagram ◽  
Standard Test ◽  
Forming Limit ◽  
Ultrasonic Vibrations ◽  
Sheet Metals ◽  
Average Grain Size ◽  
Wide Range ◽  
Ultrasonic Assisted ◽  
St14 Steel

It was recently demonstrated that ultrasonic vibrations could result in lower forming forces and a better surface finish in a wide range of metal forming processes. The Nakazima stretch-forming test is a long-established experimental procedure for the formability evaluation of sheet metals. Today, the development of a standard test is critical for assessing sheet metals’ formability enhancement due to ultrasonic vibrations, which can potentially unlock the material selection limit in various manufacturing applications. This study aims to present a method and apparatus for effectuating the forming limit diagram (FLD). At the same time, high-frequency ultrasonic vibrations are combined with the movement of the forming tool. Taking St14 steel as an example, the mechanical and microstructural properties such as formability, Micro-Vickers hardness, and grain sizes were systematically investigated. Furthermore, the conventional FLD, as well as the novel “Ultrasonic-Assisted Forming Limit Diagram” (UA-FLD), were attained and compared with a nonlinear regression-based approach. The results have indicated that superimposing ultrasonic vibrations with the amplitude of 15µm at the frequency of 20 kHz to the tool would cause a notable enhancement in forming limit diagram, a maximum of 28% increase in hardness, and a 23% reduction in average grain size of the specimens.

Finite Element Analysis of Blanking Process by Superimposing Ultrasonic Vibrations

2011 ◽  
Vol 201-203 ◽  
pp. 126-132 ◽  
Author(s):  
Wei Ching Yeh ◽  
Tsuh Siao Chu ◽  
Shiuan Sheng Wang ◽  
Kuang Hua Fuh ◽  
Kuan Hun Chen
Keyword(s):  
Finite Element ◽  
Ultrasonic Vibration ◽  
Wire Drawing ◽  
Load Flow ◽  
Ultrasonic Vibrations ◽  
Element Analysis ◽  
Finite Element Software ◽  
Punch Load ◽  
Edge Profile ◽  
Blanking Process

The application of ultrasonic vibrations superimposed on wire drawing, deep drawing, upsetting and rolling has been developed in the literature. No attempts have ever been made to develop the application of the ultrasonic vibration to blanking process. This paper reports an investigation into the effects of the superimposed ultrasonic vibrations of the die during the blanking process by finite element software DEFORM-2D. The results are compared with the conventional blanking experiment by Hatanaka and Yamaguchi [7] and the simulations are analyzed with various vibration directions, amplitudes and frequencies. The effects of the ultrasonic vibration on the punch load, flow stress and edge profile are systematically studied. The results show ultrasonic vibration can decrease the punch load and improve the quality of edge profile by increasing the vibration amplitudes and frequencies.

3D Coupled Thermomechanical Finite Element Analysis of Ultrasonic Consolidation

2007 ◽  
Vol 539-543 ◽  
pp. 2651-2656 ◽  
Author(s):  
C.J. Huang ◽  
E. Ghassemieh
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Friction Coefficient ◽  
Stress Field ◽  
Ultrasonic Wave ◽  
Ultrasonic Vibration ◽  
Softening Effect ◽  
Element Analysis ◽  
Consolidation Process ◽  
Ultrasonic Consolidation

A 3-D coupled temperature-displacement finite element analysis is performed to study an ultrasonic consolidation process. Results show that ultrasonic wave is effective in causing deformation in aluminum foils. Ultrasonic vibration leads to an oscillating stress field. The oscillation of stress in substrate lags behind the ultrasonic vibration by about 0.1 cycle of ultrasonic wave. The upper foil, which is in contact with the substrate, has the most severe deformation. The substrate undergoes little deformation. Apparent material softening by ultrasonic wave, which is of great concern for decades, is successfully simulated. The higher the friction coefficient, the more obvious the apparent material softening effect.

Numerical Simulation of Plunge Force During the Plunge Phase of Friction Stir Welding and Ultrasonic Assisted FSW

2008 ◽  
Author(s):  
Kwanghyun Park ◽  
Bongsuk Kim ◽  
Jun Ni
Keyword(s):  
Numerical Simulation ◽  
Friction Stir Welding ◽  
High Frequency ◽  
Hybrid Welding ◽  
Ultrasonic Vibrations ◽  
Welding Quality ◽  
Friction Stir ◽  
Ultrasonic Assisted ◽  
Welding Force ◽  
Welding Technique

Ultrasonic assisted friction stir welding (UaFSW) is an hybrid welding technique, where high frequency vibration is superimposed on the movement of a rotating tool. The benefit of using ultrasonic vibration in the FSW process refers to the reduction in the welding force and to the better welding quality. The UaFSW system is being developed and its mechanism needs to be understood using both the experiments and the numerical simulations. In this paper, FE simulations of FSW and UaFSW using ABAQUS/Explicit were carried out to examine plunge forces during the plunge phase of FSW and UaFSW, respectively. First, the simulations of the conventional FSW process were validated. Then, simulation of UaFSW process was performed by imposing sinusoidal horizontal ultrasonic vibrations on the tool.

Research on Milling Force in Ultrasonic Assisted End Milling of Titanium Alloy Thin-Walled Parts

2018 ◽  
Vol 764 ◽  
pp. 252-260
Author(s):  
Feng Jiao ◽  
Cheng Lin Yao ◽  
Li Zhao ◽  
Feng Qi
Keyword(s):  
Titanium Alloy ◽  
Cutting Force ◽  
Ultrasonic Vibration ◽  
End Milling ◽  
Signal To Noise Ratio ◽  
Milling Force ◽  
Alloy Material ◽  
Ultrasonic Assisted ◽  
Thin Walled ◽  
Force Characteristics

Hard machinability of titanium alloy material and poor stiffness of thin-walled part restricted the extensive applications of titanium alloy thin-walled component in aerospace engineering. In order to increase geometric accuracy, a method of ultrasonic vibration assisted (UVA) end milling technology with workpiece vibrating in feeding direction was put forward in this paper, and the corresponding milling force characteristics in UVA milling of titanium alloy TC4 thin-walled workpiece were researched. Through theoretical analysis, the path of cutter tooth in UVA milling was analyzed. The important factors that affect milling force are obtained with the signal to noise ratio analysis. Results show that the radial cutting force in UVA milling is smaller than that in traditional milling. Cutting force fluctuate in high frequency when treated ultrasonic vibration. And the axial cutting feed is the core factor that affects the milling force. The research provides a certain reference for the precision milling of titanium alloy thin-walled parts.

Schwingungsüberlagerte Kreissägewerkzeuge/Ultrasonic-assisted circular sawing

2020 ◽  
Vol 110 (01-02) ◽  
pp. 45-49
Author(s):  
Michael Raab ◽  
Christoph Birenbaum ◽  
Michael Stroka
Keyword(s):  
Cutting Tools ◽  
Cutting Process ◽  
Ultrasonic Vibrations ◽  
Vibration Behavior ◽  
Circular Saw ◽  
Ultrasonic Assisted ◽  
Circular Sawing

Der Beitrag beschreibt einen Ansatz zur simulationsgestützten Nachbildung des Schwingverhaltens dünner scheibenförmiger Werkzeuge bei hochfrequenten Wechselschwingungen. Der Ansatz wurde primär für Kreissägewerkzeuge entwickelt, um diese bereits in der Konzeptphase so zu gestalten, dass diese sich für die ultraschallüberlagerte Zerspanung bei bis zu 20 kHz einsetzen lassen.   This article describes a model which helps to recreate the vibration-behavior of thin circular-shaped cutting tools influenced by ultrasonic vibrations. The model is primarily developed for the conception of circular saw-blades to support the geometric adaption for the ultrasonic-assisted-cutting process (UAC) at 20 kHz.

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