Challenges in Designing and Processing of High Entropy Brass
摘要
Brass is one of the earliest conventional alloys being used by humankind and is among the widely utilized family of alloys for a variety of applications, including day-to-day needs. However, poor work hardenability, fatigue resistance, and engineering strength are some key issues that limit its application as a structural material. Therefore, this study aimed to revive conventional brass by adopting high entropy alloy (HEA) design route to overcome its limitations while maintaining its inherent characteristics. HEA design route was used to design and fabricate high entropy brass (HEB) with the addition of Fe, Al, Ni, and Si along with Cu and Zn as constituent elements. However, we found huge challenges in obtaining a successful melt of the HEB by conventional routes such as vacuum based melting processes. At last, moving away from vacuum-based melting route to non-vacuum-based melting technique followed by addition of constituent elements in a unique sequence resulted in successful melting of the HEB. Presence of Fe and Cu resulted in classical phase splitting resulting in Cu and Fe rich phases in as-cast microstructure whereas presence of Ni, Al and Si in Cu matrix enhanced the compressive strength of the alloy to 1.8 GPa with a fracture strain of 22% at room temperature. Tensile and corrosion behavior of the HEB needs to be explored further in order to compare its overall characteristics with brass, however, this work gives insight and direction for successful fabrication of HEB and associated challenges using the high entropy approach.