Abstract
Investment casting is a highly flexible process which was previously perceived as an expensive process. However, when the process is compared to other optional processes which may require machining or welding, this casting can produce metallic components at highly competitive costs. There are many process variables which affect the process such as die temperature, wax temperature, injection pressure, shell firing temperature and time, cooling rate. In this study, important shell parameters such as preheat temperature, firing temperature and firing time, and melt pouring temperature have been chosen as process variables influencing the quality of the hypoeutectic aluminium–silicon alloy investment casting. The optimal input parametric condition for reduction of linear and volumetric shrinkages and increment of tensile strength of Al–Si 7%–Mg investment casting has been identified as shell preheat temperature of 200 °C, firing temperature of 900 °C, firing time of 7 h and pouring temperature of 600 °C. At this optimal setting, it was found that linear and volumetric shrinkages decreased from 0.65 and 1.89% to 0.381 and 1.546%. The tensile strength of the casting increased from 96 to 121 MPa with regard to the nine experimental runs performed. Microstructural observation revealed that higher shell preheat and pouring temperatures led to augmented porosity, increased secondary dendrite arm spacing (35.53 ± 2.4 μm), larger detrimental iron-rich intermetallics (40.49 ± 25.15 μm) followed by reduced tensile properties of the casting (96 MPa).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of the Brazilian Society of Mechanical Sciences and Engineering
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.