Microstructure and properties of in-situ Al–Si/Al₂O₃ composites prepared by displacement reaction

ABSTRACT

In this work, we have studied the displacement reaction of Al and SiO₂ powder blends by mechanical alloying (MA) for 20 h and low-temperature sintering. The microstructural evolution of powder and compacted specimens were studied by X-ray diffraction and scanning electron microscopy. The extent of the milling on the displacement reaction was studied by differential thermal analysis (DTA). The results show that the reaction between Al–SiO₂ couple does not initiate after milling up to 20 h but occurs after thermal treatment of powders. DTA results indicate a lowering in the reaction temperature of Al–SiO₂ couple after milling. Following the DTA results, we densified the Al–SiO₂ powder compacts at 700°C to produce an in-situ Al–Si/Al₂O₃ composite. The physical, mechanical, and tribological performance of the composite at different milling times are also reported here.

KEYWORDS:

• Mechanical alloying
• in-situ
• displacement reaction
• sintering
• microstructure

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) [grant number 2021R1A2C1005478].

Notes on contributors

Ashutosh Sharma

Ashutosh Sharma is working as Assistant Professor in the Department of Materials Science and Engineering, Ajou University, Korea. He is an expert in lead free soldering, brazing, electrochemical plating and corrosion. His current research interests include powder metallurgy and laser additive manufacturing.

Hansung Lee

Hansung Lee is a PhD student in the Department of Energy Systems Research, Ajou University, Korea. He is working on high entropy alloys, additive manufacturing, surface engineering and powder metallurgy.

Byungmin Ahn

Byungmin Ahn is currently Professor in Department of Materials Science and Engineering and Department of Energy Systems Research, Ajou University, Korea. He also holds a position of Adjunct Research Professor in the Department of Chemical Engineering and Materials Science, University of Southern California, USA, where he received his Ph.D. degree from.