The effect of the layer deposition technique on production, structure, and properties of thick-walled elements during wire and arc additive manufacturing of parts from aluminum alloy ER5356

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.