Year-end Sale % OFF 
Abstract
Bismuth (Bi) alloying in Aluminum (Al) alloys is considered of importance in special applications requiring improvements in the alloy machining. Despite that, the influence of Bi either on evolution of the solidification or on resulting microstructure of hypereutectic Al-Si alloys is still to be determined. The present research work is devoted to these requirements. In the present study, Al-15wt.% Si hypereutectic alloy is modified with 1.0 wt.% Bi. The effects of this addition on the morphology of the phases forming the microstructure and on the tensile/wear properties are investigated. Various samples characterized by distinct cooling rates are generated by transient directional solidification of the ternary Al-Si-Bi alloy. Microstructure is examined by optical microscopy and scanning electron microscopy (SEM) analyses, segregation by energy-dispersive X-ray spectroscopy (EDS) whereas wear and tensile properties have been characterized by standardized tests. The experimental variations of the eutectic spacing are compared to each other based on their trends. It is found that the addition of minor Bi content (~1 wt. %) permitted tensile strength and ductility of 195 MPa and 14%. Furthermore, wear resistance is improved by up to 20% due to the Bi addition. The reasons for that will be outlined.
Highlights
Al-Si alloys are widely used to produce shaped castings for a variety of applications as a result of their high specific strength, wear resistance, corrosion resistance and low thermal expansion coefficient
The present study aims to contribute to a better comprehension of the effects of cohesion, size and distribution of the hard and soft phases on the mechanical properties and wear behavior of the ternary Al-15wt.%Si-1wt.%Bi alloy
This study focuses on the influence of solidification thermal parameters on the microstructural evolution
Summary
Al-Si alloys are widely used to produce shaped castings for a variety of applications as a result of their high specific strength, wear resistance, corrosion resistance and low thermal expansion coefficient. The usage of these alloys as an alternative to gray cast iron in automotive parts such as cylinder heads, brake discs and pistons aims to reduce automobile weight and improve fuel efficiency. In relation to the expanding applications of these alloys in the aeronautical and automotive industries, energy efficiency is directly associated to the weight factor, in which Al is about three times less dense than steel[4,5]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
