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    Characterization of boronized AISI 1050 steel and optimization of process parameters
    (Carl Hanser Verlag, 2019) Boztepe, Mete Han; Bayramoglu, Melih; Uzay, Cagri; Dagsuyu, Cansu; Kokangul, Ali; Geren, Necdet
    In this study, AISI 1050 steel was boronized at temperatures of 800, 850, 900, 950 and 1000 degrees C for 3, 6, and 9 hours by means of a pack boronizing process. The formation of the boride layer was investigated. The characterization of the boronized surfaces was determined by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Although dual phase, FeB and Fe2B were observed in the boride layer, the intensity of the FeB was slight and collected only near the outer surface which is the desired structural morphology. As the boronizing temperature and holding time strongly affect the results of both boride layer thickness and the surface hardness of the material, multi-objective mathematical models were developed for optimization. Energy consumption during boronizing was also considered. Hence, the optimum values for both temperature and holding time were determined, both of which maximize surface hardness and boride layer thickness while minimizing energy consumption.
  • [ X ]
    Öğe
    Evaluating the performance of Bi58Sn42 mold produced by material extrusion additive manufacturing system for agile manufacturing
    (Emerald Group Publishing Ltd, 2024) Delibas, Hulusi; Geren, Necdet
    PurposeThe purpose of this study is to produce a low-cost sheet metal forming mold made from the low melting point Bi58Sn42 (bismuth) alloy by using an open-source desktop-type material extrusion additive manufacturing system and to evaluate the performance of the additively manufactured mold for low volume sheet metal forming. Thus, it was aimed to develop a fast and inexpensive die tooling methodology for low-volume batch production.Design/methodology/approachInitially, the three-dimensional printing experiments were performed to produce the sheet metal forming mold. The encountered problems during the performed three-dimensional printing experiments were analyzed. Accordingly, both tunings in process parameters (extrusion temperature, extrusion multiplier, printing speed, infill percentage, etc.) and customizations on the extruder head of the available material extrusion additive manufacturing system were made to print the Bi58Sn42 alloy properly. Subsequently, the performance of the additively manufactured mold was evaluated according to the dimensional change that occurred on it during the performed pressing operations.FindingsResults showed that the additively manufactured mold was rigid enough and proved to have sufficient strength in sheet metal forming operations for low-volume production.Originality/valueAlternative mold production was carried out using open-source material extrusion system for low volume sheet metal part production. Thus, cost effective solution was presented for agile manufacturing.