Abstract
Various mechanical components such as piston, cylinder blocks, brakes and drums, have to operate under high temperature condition during their service life. Therefore, to meet the demand of high strength materials, a detailed analysis of their synthesis and high temperature tensile behaviour is of utmost importance. Present study is an effort in this direction to develop AA5052/9vol. %ZrB2 insitu composite by salt-metal reaction technique. An insitu reaction between molten aluminium alloy and two inorganic salts K2ZrF6 and KBF4 begins at 860°C and continues up to 30 min. The resulting reaction product ZrB2 is desired reinforcement confirmed by XRD analysis. Microstructural study was performed to analyse grain size, particle morphology, and their distribution in the matrix. Tensile tests were conducted at temperatures ranging from room temperature (RT) to 200°C with an interval of 50oC. The results revealed the decreasing trend of UTS and YS (0.2% off set) with increase in temperature; however ductility increased with temperature. The composite is able to maintain about 81% of its ambient temperature strength at 150°C and 72% at 200°C. Strain hardening exponent was not significantly affected with temperature and tensile properties were correlated with fractured surface morphology examined under SEM to understand the mechanism.
Highlights
Particulate aluminium matrix composites (PAMCs) are widely used for manufacturing of various mechanical components such as piston, cylinder brakes, discs/drums and piston insert rings, due to their high strength to weight ratio, good thermal and electrical conductivity, good corrosion and wear resistance characteristics[1,2]
AA5052 alloy has been reinforced with 9 vol % ZrB2 particles by insitu synthesis
Cylindrical specimens for high temperature tensile testing were prepared according to BS 12-1950 British standards and tested on a computerized 100 kN screw-driven InstronTM Universal Testing Machine at temperatures ranging from room temperature (RT) to 200°C at a constant strain rate of 1.07/ 10-3 s-1
Summary
Particulate aluminium matrix composites (PAMCs) are widely used for manufacturing of various mechanical components such as piston, cylinder brakes, discs/drums and piston insert rings, due to their high strength to weight ratio, good thermal and electrical conductivity, good corrosion and wear resistance characteristics[1,2]. Sahoo and Koczak[16], prepared Al-4.5wt.%Cu/TiC insitu composites and studied the tensile properties at elevated temperature They observed that yield strength and tensile strength of composites were improved by 130% and 65% respectively when compared with Al-4.5wt. Hoseini and Meratian[18] studied the tensile properties of insitu aluminium alumina composites at ambient as well as at high temperature They observed that effect of alloying elements on strengthening was more. Yi et al.[19] studied the high temperature mechanical properties of insitu TiB2p reinforced Al-Si alloy composites and reported that tensile strength of composites were higher than Al-Si master alloy at temperatures ranging from 25° to 400°C. Oñoro[20] studied high temperatures mechanical properties of TiB2 particles reinforced AMCs based on aluminium alloys (6061 and 7015) up to 500°C. Tensile results are correlated with morphology of fractured surface to understand the mechanism of failure at elevated temperature
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.