Ultrasonic energy is introduced into the Metal Inert Gas (MIG) welding arc and weld pool by superposition of an ultrasonic frequency current. In this study, the arc shape, arc energy, and ultrasonic energy that responded to ultrasonic excitation voltage and frequency is investigated. The comprehensive influence of arc and ultrasonic energy on weld formation, microstructure, and mechanical properties is further studied. The arc and ultrasonic energy are analyzed by using a high-speed camera and microphone, respectively. The results showed that the arc width increased, and the arc energy density decreased after the superposition of ultrasonic current. The arc height could be compressed under certain ultrasonic excitation parameters. The ultrasonic excitation voltage and frequency had a direct influence on the ultrasonic energy. The arc height, arc energy density, and ultrasonic energy together determined the weld width. Ultrasound could effectively refine the microstructure of the weld zone and fusion zone but had little effect on the heat-affected zone. Ultrasound improved the hardness of the joint by refining the grain and the second phase. The joint hardness was the highest when the ultrasonic excitation voltage was 100 V, and the frequency was 30 kHz.
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http://dx.doi.org/10.3390/ma14174884 | DOI Listing |
Int J Biol Macromol
January 2025
College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Zhejiang Key Laboratory of Green, Low-carbon and Efficient Development of Marine Fishery Resources, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China. Electronic address:
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View Article and Find Full Text PDFHeliyon
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Department of Nanotechnology, Faculty of New Sciences and Technologies, Semnan University, Semnan, Iran.
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View Article and Find Full Text PDFInt J Surg
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Department of Surgery, Sapienza University of Rome, Rome.
Background: One of the most important surgical steps during thyroidectomy is the safe ligation of vessels. In fact, it is crucial to avoid postoperative bleeding and nerves' injury. The "clamp and tie" technique was first introduced in the 19th century.
View Article and Find Full Text PDFSci Rep
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Udmurt Federal Research Center of the Ural Branch of RAS, Baramzina str. 34, Izhevsk, 426067, Russia.
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State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Central South University, Changsha 410083, China; Light Alloy Research Institute, Central South University, Changsha 410083, China.
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