Darya Volosevich

BACKGROUND: Additive manufacturing involves the creation of three-dimensional objects with layer-by-layer application of additive material. There are many additive manufacturing technologies, each differing in consumables, manufacturing speed, surface quality of the resulting sample, power source, etc. One of these is the arc-directed energy deposition technology. Arc-directed energy deposition is an additive manufacturing technology that uses electric arc energy as a heat source to melt additive material. It is widely used in contemporary mechanical engineering due to its high productivity and wide range of materials, especially in the manufacturing of special equipment and components of complex shapes, where conventional techniques are not effective enough. AIM: This work aimed to design, manufacture, and test an arc torch Interface for an industrial robotic arm flange using arc-directed energy deposition. METHODS: We used welding wire made of AlMg5 alloy and high-purity argon as a shielding gas. For manufacturing, we used a process system based on a Fanuc M-710iC robot arm and a Fronius TPS500i welding power source with a cold metal transfer capability. Experiments were conducted to select manufacturing conditions and strategies to ensure high quality of the test piece and minimize defects. The manufactured pieces underwent metallography and mechanical tests. RESULTS: A range of standard manufacturing conditions has been selected. The chosen manufacturing strategy allowed to reduce anisotropy and avoid incomplete fusion. Mechanical tests showed that the properties of the deposited material exceed the requirements of GOST 17232-99. The study allowed to design, manufacture, and assemble an interface that meets the specified rigidity and dimensional criteria. CONCLUSION: The study showed the effectiveness of manufacturing arc torch interfaces for robotic arm flanges using arc-directed energy deposition. The developed method allows to manufacture complex shape products with the required mechanical properties, which corroborates the potential of arc-directed energy deposition in mechanical engineering.

BACKGROUND: Today, aluminum alloys are applied in many industries, including aerospace, shipbuilding, chemical, mechanical engineering, etc. Wire and arc manufacturing used to produce aluminum alloy products saves much time and cost. A big problem related to additive technologies is the anisotropy of properties. Tensile properties are usually higher along the deposition path (X axis) than the manufacturing path (Z axis). One way to reduce the anisotropy is to use alternative growth strategies. This study aims to establish the dependence of material properties on the layer deposition strategy. AIM: The article investigates the effect of the layer deposition technique on production, structure and properties of thick-walled elements during wire and arc additive manufacturing from aluminum alloy ER5356. MATERIALS AND METHODS: For this purpose, samples were manufactured with the following deposition techniques: linear oscillations normal to the manufacturing path; linear oscillations at a 45-degree angle to the manufacturing path; elliptical oscillations along the manufacturing path, and a zigzag normal to the manufacturing path. The article explores the structure and mechanical properties of samples made by wire and arc additive manufacturing with different filling techniques. RESULTS: For developing a strategy with linear oscillations at a 45-degree angle to the manufacturing path (Strategy 2) and elliptical oscillations along the manufacturing path (Strategy 3), there were unstable areas at the start/end points of the process. The lateral surface quality of samples 2, 3 and 4 is the same; whereas sample 1 has more pronounced ripples. The least anisotropy of 4% was achieved using the first strategy. For the other three strategies, this value varied from 10.2 to 14.2%. Porosity of the samples for all four strategies did not exceed 1% of the cross-sectional area. Deteriorated mechanical properties along the Z axis are associated with brittle phases at the layer boundaries (strategies 2 and 3) and the incomplete fusion of layers (strategy 4). CONCLUSIONS: The results show that a stable structure is produced only by techniques with linear oscillations normal to the manufacturing path and with a zigzag motion. In the other two cases, unstable areas at the edges of the sample are observed. Moreover, the quality of the side surface is similar in all four samples. In addition, it is worth noting that a required level of mechanical properties with low anisotropy was achieved only with the strategy providing for linear oscillations normal to the manufacturing path.

In this study, a composite with alternate layers of 5056 and 1580 alloys was manufactured with wire arc additive manufacturing technology. It is shown that increased strength characteristics of composite material can be obtained with deformation treatment using a high-pressure torsion (HPT) technique. The microstructure and mechanical properties of the HPT-processed material in different structural states were investigated. The HPT-processed material exhibits a high value of ultimate tensile strength (~770 MPa) but low ductility. Short-term annealing at 250 °C and additional deformation with HPT to 0.25 of revolution at room temperature resulted in a slight decrease in the material’s strength to ~700 MPa but provided ductility of ∼9%. Physical mechanisms to improve plasticity in correlation with microstructure evolution are discussed.

In recent years, additive manufacturing of products made from 5000 series alloys has grown in popularity for marine and automotive applications. In this work, we compare of mechanical properties characteristics of aluminum alloy 5056 material produced by wire-arc additive technology and rolling. We carried out tension tests under quasi-static loading and impact toughness tests under impact loading. The results show that upon similar ultimate tensile strength and ductility, material after additive manufacturing demonstrates decreased resistance against dynamic loading than material manufactured by the typical method of casting and rolling. This decrease in properties was explained through macro- and microstructure analysis.

In this study composite with alternate layers of 5056 and 1580 alloys was manufactured by wire arc additive manufacturing technology. It is shown that increased strength characteristics of composite material can be obtained due to deformation treatment by high-pressure torsion (HPT) technique. The microstructure and mechanical properties of the HPT-processed material in different structural states were investigated. The HPT-processed material exhibits high value of ultimate tensile strength (~ 770 MPa) but low ductility. Short-term annealing at 250 oС and additional deformation by HPT to 0.25 of revolution at room temperature resulted in a slight decrease in material’s strength to ~ 700 MPa but provided ductility ∼ 9%. Physical mechanisms to improve plasticity in correlation with microstructure evolution is discussed.