Enhancement of Tensile Properties of Low-Pressure Die Casting Aluminum Alloy Having Halfly Scrap Via Ultrasonic Degassing Method

Abstract

There are studies in the literature on metal cleanliness, but unfortunately, many of them do not comply with environmental regulations such as using more cleaner procedures, having a lower carbon footprint, etc. This study was majorly involved adding 50% primary ingots and 50% machining chip to the liquid baths to investigate the more effective use of scrap as raw material. The bifilm index was used to quantify liquid metal cleaning, and in order to settle for with regulations, the ultrasonic degassing method (UST) was carried out with two different durations of 90 s and 180 s to examine the change in melt quality without adding any salt flux, the increase in metal cleanliness and how this increase could be examined in terms of mechanical properties. While the values of yield and tensile strength had high regression coefficients of R2 = 0.94 and 0.93, respectively, the elongation at break values reached a much more reliable regression coefficient of R2 = 0.9998, and the equations corresponding to the obtained second-degree polynomials were shared. As a result, it has been concluded that the mechanical properties of the cast materials namely values of strength of yield, tensile and elongation at break could be increased in the as-cast conditions to roughly 130 MPa, 190 MPa and 4%, respectively with lowered bifilm index to 40 mm, thus this scenario shows that increasing tensile properties could be significantly procured with a decrease in the bifilm index.

Keywords

• Ultrasonic degassing
• Tensile test
• Mechanical properties
• Low-pressure die-casting

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