Investigating ultrasound-induced acoustic softening in aluminum and its alloys

Ultrasonics ◽  
2020 ◽  
Vol 102 ◽  
pp. 106005 ◽  
Author(s):  
Q. Mao ◽  
N. Coutris ◽  
H. Rack ◽  
G. Fadel ◽  
J. Gibert
Keyword(s):  
Acoustic Softening

Direct Evidence for Acoustic Softening and Residual Hardening

2019 ◽  
Author(s):  
Yanying Hu ◽  
Huijie Liu ◽  
Hidetoshi Fujii ◽  
Hideki Araki ◽  
Kazuki Sugita ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Acoustic Softening

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.

Analytical Prediction and Experimental Investigation of Burnishing Force in Rotary Ultrasonic Roller Burnishing Titanium Alloy Ti–6Al–4V

2020 ◽  
Vol 142 (3) ◽  
Author(s):  
Jian Zhao ◽  
Zhanqiang Liu ◽  
Bing Wang ◽  
Yukui Cai ◽  
Qinghua Song
Keyword(s):  
Titanium Alloy ◽  
Prediction Model ◽  
Milling Process ◽  
Analytical Prediction ◽  
Ultrasonic Power ◽  
Machined Surface ◽  
Softening Effect ◽  
Force Prediction ◽  
Contact Width ◽  
Acoustic Softening

Abstract Ultrasonic burnishing is usually applied to make machined surface modification. The acoustic softening effect caused by ultrasonic vibration is beneficial to the machining of difficult-to-cut materials. In the present work, a burnishing force prediction model was proposed for rotary ultrasonic burnishing of titanium alloy Ti–6Al–4V, whose surface had been machined with the face milling process. Firstly, the contact between the burnishing roller and one single milling mark was analyzed with plane strain assumption based on the Boussinesq–Flamant contact problem. Then, the effect of ultrasonic softening on the yield stress of Ti–6Al–4V was investigated. The critical contact width and contact load that the burnishing roller crushed on one single milling mark were examined to confirm the feasibility of the proposed ultrasonic burnishing force prediction model. The experimental verifications were carried out at various ultrasonic powers. The burnishing forces from experiment measurements were consistent with the calculated results from the proposed model. The mean deviations between theoretical and experimental results of the ultrasonic burnishing force were 10.4%, 12.2%, and 15.2%, corresponding to the ultrasonic power at the level of 41 W, 158 W, and 354 W, respectively.

Theoretical and FE Analysis of Ultrasonic Welding of Aluminum Alloy 3003

2009 ◽  
Vol 131 (4) ◽  
Author(s):  
A. Siddiq ◽  
E. Ghassemieh
Keyword(s):  
Aluminum Alloy ◽  
Welding Process ◽  
Surface Friction ◽  
Material Model ◽  
Weld Interface ◽  
Ultrasonic Welding ◽  
Thin Layers ◽  
Consolidation Process ◽  
Acoustic Softening ◽  
Number Of Cycles

Ultrasonic welding (consolidation) process is a rapid manufacturing process that is used to join thin layers of metal at low temperature and low energy consumption. Experimental results have shown that ultrasonic welding is a combination of both surface (friction) and volume (plasticity) softening effects. In the presented work, an attempt has been made to simulate the ultrasonic welding of metals by taking into account these effects (surface and volume). A phenomenological material model has been proposed, which incorporates these two effects (i.e., surface and volume). The thermal softening due to friction and ultrasonic (acoustic) softening has been included in the proposed material model. For surface effects, a friction law with variable coefficient of friction that is dependent on contact pressure, slip, temperature, and number of cycles has been derived from experimental friction tests. The results of the thermomechanical analyses of ultrasonic welding of aluminum alloy have been presented. The goal of this work is to study the effects of ultrasonic welding process parameters, such as applied load, amplitude of ultrasonic oscillation, and velocity of welding sonotrode on the friction work at the weld interface. The change in the friction work at the weld interface has been explained on the basis of softening (thermal and acoustic) of the specimen during the ultrasonic welding process. In the end, a comparison between experimental and simulated results has been presented, showing a good agreement.

Effects of Acoustic Softening and Hardening in High-Frequency Vibration-Assisted Punching of Aluminum

2014 ◽  
Vol 29 (10) ◽  
pp. 1184-1189 ◽  
Author(s):  
A. T. Witthauer ◽  
G. Y. Kim ◽  
L. E. Faidley ◽  
Q. Z. Zou ◽  
Z. Wang
Keyword(s):  
High Frequency ◽  
High Frequency Vibration ◽  
Acoustic Softening

Investigating Ultrasound-Induced Acoustic Softening of Aluminum 6061

2014 ◽  
Author(s):  
Qing Mao ◽  
James M. Gibert ◽  
Georges Fadel
Keyword(s):  
Stress Reduction ◽  
Experimental Studies ◽  
Tensile Tests ◽  
Ultrasonic Waves ◽  
Test Machine ◽  
Acoustic Softening ◽  
Softening Process ◽  
Noise Factors ◽  
Longitudinal Ultrasonic Waves ◽  
Energy Activation

Blaha and Langenecker are the first to document the phenomena known as “acoustic softening”: a significant reduction of static stress in tensile tests when applying longitudinal ultrasonic waves to various metals. Based on experimental observations, they hypothesized that acoustic heating due to internal friction and energy activation at dislocations was responsible for this temporary weakening of the material. Later research studies investigating the acoustic softening process used different experimental setups leading to alternative theories of the softening process such as superposition of static and dynamic stress. The variation in the design of the experiments leads to significant differences in observations, causing differing interpretations of the results and the formation of competing theories. We reviewed previous experimental studies and found that the optimum setup is similar to Blaha’s and Langenecker’s. Their setup minimizes noise factors such as friction at the oscillator specimen interface, which could contribute to heating and stress reduction. Therefore, we present our experimental setup composed of an MTS tensile test machine and a Branson ultrasonic welder to study the softening of aluminum 6061 and discuss our own results and how they compare with those in the literature. Additionally, we investigate the applicability of competing theories of softening based on our experimental data.

scholarly journals Influence of Vibrational Loading on Deformation Behavior of Metallic Glass: A Molecular Dynamics Study

Metals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1197 ◽  
Author(s):  
Mao Zhang ◽  
Qiaomin Li ◽  
Jiacheng Zhang ◽  
Xinyun Wang ◽  
Junsong Jin ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Metallic Glass ◽  
High Frequency ◽  
Deformation Behavior ◽  
Elastoplastic Deformation ◽  
Accelerated Aging ◽  
Vibrational Loading ◽  
Average Deformation ◽  
Acoustic Softening ◽  
Β Relaxation

The influence of vibrational loading on the deformation behavior of a Zr50Cu46Al4 metallic glass (MG) was characterized via molecular dynamics approaches. High-frequency (1 GHz) vibrational loading was imposed on the elastoplastic deformation stage during the uniaxial tension of the MG conducted at 50 K. It was found that imposing vibrational loading scarcely reduces the average deformation resistance. On the contrary, it results in a notable residual hardening effect after the vibrational loading is removed, which differs significantly from the previously reported acoustic softening mechanisms. Vibrational loading can increase the fraction of STZed atoms and enhance the shear localization degree, which is beneficial to the shear deformation of MGs. Meanwhile, the influence of vibrational loading on the local microstructure of MG is negligible. A plausible explanation of these phenomena is given by considering the accelerated aging of MG stemming from the β relaxation.

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

Value of a second seismic monitor in late stages of field development at Holstein

2020 ◽  
Vol 39 (1) ◽  
pp. 53-61
Author(s):  
Mehdi Zouari ◽  
Maria Perez ◽  
Jianxiong Chen ◽  
Allison Kimbrough ◽  
Lauren Salathe ◽  
...  
Keyword(s):  
Water Saturation ◽  
Injection Pressure ◽  
Reservoir Pressure ◽  
Amplitude Variation With Offset ◽  
Field Development ◽  
Northern Portion ◽  
Acoustic Softening ◽  
Low Levels ◽  
Technology Group ◽  
Late Stages

A second seismic monitor survey acquired after nine years of production at Holstein Field was used successfully to define new wellbore sidetracks to target unswept areas in two of the main producing reservoirs (J2 and K1). The asset team and the technology group worked together to investigate the quality and interpretability of the 4D signal between the first and second monitor surveys. The method consisted of conducting a quality check of the acquisition and processing steps, modeling the amplitude variation with offset responses using existing wells to determine the response to fluid effects, and finally extracting and creating amplitude difference maps between monitor surveys for each reservoir. The interpretation of the 4D amplitude differences, combined with the analysis of production and pressure data from historical injector and producer wells, resulted in the decision to target what was interpreted to be a partially swept J2/K1 reservoir compartment by the aquifer in the southern part of the field. Well #12 was drilled in that target and encountered oil pay in both reservoirs, with low levels of water saturation. Another J2 area in the northern part of the field was interpreted to have remained partially unswept by water injectors, although seismic acoustic softening over that portion of the field suggested that it was still benefiting from injection pressure support. Well #11 was drilled in that northern portion of the field and encountered an oil-bearing reservoir with water saturation near preproduction levels and a reservoir pressure approaching original reservoir pressure, hence confirming repressurization.

Sign in / Sign up

Export Citation Format

Share Document