Effects of Ultrasonic Vibration on Microstructure, Mechanical Properties, and Fracture Mode of Inconel 625 Parts Fabricated by Cold Metal Transfer Arc Additive Manufacturing

Wire and arc additive manufacturing based on cold metal transfer (WAAM-CMT) has aroused wide public concern in recent years as one of the most advanced technologies for manufacturing components with complex geometries. However, the microstructure and mechanical properties of the parts fabricated by WAAM-CMT technology mostly are intolerable for engineering application and should be improved necessarily. In this study, heat treatment was proposed to optimize the microstructure and enhance mechanical properties in the case of AlSi7Mg0.6 alloy. After heat treatment, the division between coarse grain zone and fine grain zone of as-deposited samples seemed to disappear and the distribution of Si and Mg elements was more uniform. What is more, the yield strength and ultimate tensile strength were improved significantly, while the ductility could be sustained after heat treatment. The improvement of strength is attributed to precipitation strengthening, and the shape change of Si phase. No reduction in ductility is due to the higher work hardening rate caused by nanostructured precipitate. It is proved that heat treatment as an effective method can control the microstructure and enhance comprehensive mechanical properties, which will boost rapid development of WAAM industrial technology.

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Microstructure and mechanical properties of AZ91 Mg alloy fabricated by cold metal transfer additive manufacturing

Materials Letters ◽

10.1016/j.matlet.2020.128185 ◽

2020 ◽

Vol 276 ◽

pp. 128185 ◽

Cited By ~ 1

Author(s):

Ji Bi ◽

Junqi Shen ◽

Shengsun Hu ◽

Yahui Zhen ◽

Fengliang Yin ◽

...

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Metal Transfer ◽

Mg Alloy ◽

Cold Metal Transfer ◽

Microstructure And Mechanical Properties ◽

Cold Metal

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Microstructure and mechanical properties of as-built and heat-treated Ti-6Al-4V alloy prepared by cold metal transfer additive manufacturing

Journal of Manufacturing Processes ◽

10.1016/j.jmapro.2019.04.012 ◽

2019 ◽

Vol 42 ◽

pp. 41-50 ◽

Cited By ~ 11

Author(s):

Jian Gou ◽

Junqi Shen ◽

Shengsun Hu ◽

Yinbao Tian ◽

Ying Liang

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Metal Transfer ◽

Cold Metal Transfer ◽

Microstructure And Mechanical Properties ◽

Heat Treated ◽

Cold Metal

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Development of a New Cold Metal Transfer Arc Additive Die Manufacturing Process

Advances in Materials Science and Engineering ◽

10.1155/2021/9353820 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

An Zhang ◽

Yanfeng Xing ◽

Fuyong Yang ◽

Xiaobing Zhang ◽

Hongze Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Manufacturing Process ◽

Molten Pool ◽

High Efficiency ◽

Metal Transfer ◽

Cold Metal Transfer ◽

Average Grain Size ◽

Columnar Grains ◽

Cold Metal

Due to its high efficiency, cold metal transfer (CMT) arc additive manufacturing presents considerable potential in the aluminium alloy additive manufacturing industry. However, during CMT arc additive manufacturing, the surrounding air environment promotes the lateral flow of liquid aluminium and the instability of the molten pool, reduces the surface quality and material utilisation of deposition walls, and causes internal hydrogen pores and coarse columnar grains, which negatively affect the structure and mechanical properties of the deposition walls. This study developed a CMT arc additive die manufacturing process to control the substrate material and deposition path to improve the physical properties of the deposition wall. The experimental results indicated that the copper plates can affect molten pool flow and material formation in the additive process, minimise hydrogen pores, and refine columnar grains. The porosity dropped from 2.03% to 0.93%, and the average grain size decreased from 16.2 ± 1.4 to 13.6 ± 1.3 μm, thereby enhancing the structure and mechanical properties of the deposition wall to attain standard additive manufacturing products.

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On the Effect of Heat Input and Interpass Temperature on the Performance of Inconel 625 Alloy Deposited Using Wire Arc Additive Manufacturing–Cold Metal Transfer Process

Metals ◽

10.3390/met12010046 ◽

2021 ◽

Vol 12 (1) ◽

pp. 46

Author(s):

Chengxun Zhang ◽

Zhijun Qiu ◽

Hanliang Zhu ◽

Zhiyang Wang ◽

Ondrej Muránsky ◽

...

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Heat Input ◽

Inconel 625 ◽

Heat Accumulation ◽

Cold Metal Transfer ◽

Inconel 625 Alloy ◽

Cold Metal ◽

Wire Arc Additive Manufacturing ◽

Interpass Temperature

Relatively high heat input and heat accumulation are treated as critical challenges to affect the qualities and performances of components fabricated by wire arc additive manufacturing (WAAM). In this study, various heat inputs, namely 276, 552 and 828 J/mm, were performed to fabricate three thin-wall Inconel 625 structures by cold metal transfer (CMT)-based WAAM, respectively, and active interpass cooling was conducted to limit heat accumulation. The macrostructure, microstructure and mechanical properties of the produced components by CMT were investigated. It was found that the increased heat input can deteriorate surface roughness, and the size of dendrite arm spacing increases with increasing heat input, thus leading to the deterioration of mechanical properties. Lower heat input and application of active interpass cooling can be an effective method to refine microstructure and reduce anisotropy. This study enhances the understanding of interpass temperature control and the effectiveness of heat inputs for Inconel 625 alloy by WAAM. It also provides a valuable in situ process for microstructure and mechanical properties’ refinement of WAAM-fabricated alloys and the control of heat accumulation for the fabrication of large-sized structures for future practical applications.

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Effect of Casting and Additive Manufacturing on the Microstructure and Mechanical Property of Al-Cu Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.993.718 ◽

2020 ◽

Vol 993 ◽

pp. 718-722

Author(s):

Shuang Lei ◽

Ya Qi Deng ◽

Xian Feng Li ◽

Liang Wu ◽

Yan Chi Chen

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Additive Manufacturing ◽

Electron Beam Melting ◽

High Hardness ◽

Metal Transfer ◽

Heat Sources ◽

Cold Metal Transfer ◽

Cold Metal ◽

Microstructure And Mechanical Property

The TiB2 reinforced Al-5Cu composites was manufactured by additive manufacturing with two kind of heat sources, i.e., cold metal transfer (CMT) and electron beam melting (EBM). The TiB2 particles were in nano-sized with some submicron-sized particle clusters , and their morphologies were round and near round without sharp angles. It was found that the introduce of TiB2 particles improved the mechanical properties of Al-5Cu alloy obviously. The results demonstrated that both the additive manufacturing methods of cold metal transfer (CMT) and electron beam melting (EBM) could improve the microstructure of the composites significantely. Compared with the traditional casting, Al-5Cu alloy the grain sizes of the TiB2 reinforced Al-5Cu composites decreased from larger than 100 μm to 40 μm with CMT process and 25 μm with EBM process. The hardness of the TiB2 reinforced Al-5Cu composites with EBM after heat treatment could be reached to 153 HV10. The refined grains and high hardness of the TiB2 reinforced Al-5Cu composites with EBM additive manufacturing technique verified that AM technology is a promising way to optimize the microstructure and mechanical properties of Al-Cu composites.

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Comparative analysis of structure and mechanical properties of parts produced by electron-beam additive manufacturing and cold metal transfer

Izvestiya Vuzov Tsvetnaya Metallurgiya (Proceedings of Higher Schools Nonferrous Metallurgy) ◽

10.17073/0021-3438-2020-4-65-73 ◽

2020 ◽

pp. 65-73

Author(s):

A. A. Eliseev ◽

V. R. Utyaganova ◽

A. V. Vorontsov ◽

V. V. Ivanov ◽

V. E. Rubtsov ◽

...

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Comparative Analysis ◽

Additive Manufacturing ◽

Heat Removal ◽

Metal Transfer ◽

Accelerated Cooling ◽

Beam Power ◽

Cold Metal Transfer ◽

Cold Metal

Currently, the most prospective industry development areas are prototyping and additive manufacturing. In contrast to more precise powder technologies, faster wire technologies providing non-porous products are of great interest. This paper contains a comparative analysis of the effect of two wire technologies – electron-beam additive manufacturing and cold metal transfer – on the structure and mechanical properties of Aluminum Alloy 5056. Electron beam power is close to arc power at optimal printing parameters, but cold metal transfer is cheaper due to the impulse nature of the arc. In addition, the arc method is implemented in an argon atmosphere, and this accelerates the applied layer cooling. In general, the grain structure of the material is refined due to the lower heat transfer and accelerated cooling. This results in increased strength and microhardness. The constant heat removal from the substrate and the increase in the product weight change thermal conditions of the following layer. This is controlled by beam/arc powder reduction, but each layer has its own thermal history affecting the structure and properties. In particular, the more heat is transferred to the layer from the previous layers, the less strong it is. When a certain height (about 30 mm) is passed, cooling is intensified by the large mass of the product and the strength is increased again. This is most characteristic for cold metal transfer. However, these fluctuations are rather small. Mechanical properties along the growth direction are highly stable in both technologies. Cold metal transfer also shows less alloying magnesium burn-off. In general, currently the cold metal transfer technology is more cost effective and provides better quality products.

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