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MFGE 2531 2018 FallFinal ReportMaterial Property Testing of Weld Sample Material Property Testing of WeldManufacturing Engineering DepartmentGeorgia Southern University11/26/2018Objective The purpose of the lab was to study the different microstructures, hardnesses and tensile properties of a welded sample with low-carbon steel. There were different microstructures depending on the area of the weld, the base structures of the metal and the HAZ (heat affected zone). The welded sample was then placed in the tensile test machine and tested for stress and strain of the welded section.IntroductionAll the tests were performed on a sample with a MIG style welding joint. Metal inert gas welding uses an electrode mixed with inert gas to melt low carbon steel joints. The weld pool and the material (assumed tobe 1018 steel) was tested on the rockwell hardness tester. This shows how the hardness of the ferrite and pearlite phases were affected by the cooling rates of the steel affected by the heat from the MIG weld. Hardness testing was used to determine the strength of the weld, HAZ, and base metal, and how they differed. The cooling rates of the different areas are affected by how far from the heated weld the areas were. A tensile test was performed to show how much stress and strain the welded section can endure before breaking. A good sample should have broken on the steel base plate while the weld remained intact. Metallography was used to find the microstructures of the 3 fusion zones, varying between phases of ferrite and pearlite (ferrite + cementite).Experimental ProcedureFor the tensile test, one weld sample was placed into the clamps of a hydraulic tensile frame (ADMET) and then positioned vertically. The machine was then activated and the sample was put under a very smallpreload, allowing the slack to be taken out of the sample and the machine to be zeroed. Unfortunately since the weld was done on both sides, it was difficult for the machine to fracture. The part was then un-clamped and removed safely and the data was extracted via USB.