This document compares the fracture surface characteristics of tensile and impact fractures in a material, based on the direction of wire arc additive manufactured aluminum alloy wire - AlSi5. The specimens used were cut from a welded wall and subsequently loaded parallel and perpendicular to the direction of the welded layers, respectively. Scanning electron microscope (SEM) analysis of the fracture surfaces was conducted using a high depth of field scanning electron microscope. The microstructural characteristics of the fracture surfaces were examined. The analysis results affirmed the toughness of the fractured material, regardless of the test type or the orientation of the test piece concerning the build direction of the product. No significant differences were observed between specimens cut parallel and perpendicular to the welding layers. Additional observations among individual specimens reveal that specimens fractured by impact testing exhibited a 200% higher frequency and 164% larger diameter of gas pores compared to specimens fractured by tensile testing. Consequently, the average diameter of gas pores on the fractured surfaces measured 39.49 ± 13.12 µm after the tensile test and 65.00 ± 22.41 µm after the impact test. This discrepancy can be attributed to the distinct manner in which the test specimens were manufactured and tested. The wall from which the impact test specimens were extracted utilized filler welds to attain the necessary specimen width, which led to a greater introduction of impurities into the specimen and heightened exposure of the weld to the atmosphere.
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