Strength is an important specification for the forged part. This research investigates the macrostructure and grain flow distribution of material during the hot closed-die forging process of an AA7075 part by using variable flash thickness dies. Experimental tests were performed using operational conditions based on the finite volume simulation results of the forging process. The grain flow pattern and the strength of the produced parts were evaluated by using optical microscope after etching and tensile tests, respectively. It shows that using a variable flash thickness die can significantly increase the tensile strength of the forged parts.
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