Publications by authors named "Carter Hamilton"
Article Synopsis
- * The weld microstructures were analyzed using various microscopy techniques, revealing fine, equiaxed grains and distinct features between the advancing and retreating sides of the welds.
- * Mechanical tests showed that the 280/280 welds had higher tensile strengths but lower hardness compared to the 450/450 welds, and the fracture behavior differed significantly, with 280/280 showing ductile failure versus the quasi-brittle failure of 450/450.
Article Synopsis
- A novel dual-speed friction stir welding (FSW) tool was used to weld cast magnesium AZ91 and wrought aluminum 6082-T6, allowing for separate control of shoulder and pin rotation speeds.
- The study compared welds created with the dual-speed tool against those made with a conventional tool, finding that the new tool helped mitigate the brittle eutectic phase responsible for cracking.
- Experimental trials identified crucial parameters for high-quality welds, showing that maintaining a minimum material flow rate and controlling the percentage of the weld area exceeding the eutectic temperature lead to defect-free results.
For the friction stir welding (FSW) of AZ91 magnesium alloy, low tool rotational speeds and increased tool linear speeds (ratio 3.2) along with a larger diameter shoulder and pin are utilized. The research focused on the influence of welding forces and the characterization of the welds by light microscopy, scanning electron microscopy with an electron backscatter diffraction system (SEM-EBSD), hardness distribution across the joint cross-section, joint tensile strength, and SEM examination of fractured specimens after tensile tests.
View Article and Find Full Text PDFWire arc additive manufacturing (WAAM) is capable of rapidly depositing metal materials thus facilitating the fabrication of large-shape metal components. However, due to the multi-process-variability in the WAAM process, the deposited shape (bead width, height, depth of penetration) is difficult to predict and control within the desired level. Ultimately, the overall build will not achieve a near-net shape and will further hinder the part from performing its functionality without post-processing.
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