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Synthesis and characterization of Al-Si 3 N 4 nanocomposites processed by microwave sintering process Dr. Abdul Shakoor Assistant Professor Center for Advanced Materials (CAM) Qatar University, Doha, Qatar Email: shakoor@qu.edu.qa. Outline of the Presentation. Introduction
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Synthesis and characterization of Al-Si3N4 nanocomposites processed by microwave sintering process Dr. Abdul Shakoor Assistant Professor Center for Advanced Materials (CAM) Qatar University, Doha, Qatar Email: shakoor@qu.edu.qa
Outline of the Presentation • Introduction • What are Composites? • Classification of Composites • Applications of Composites • Aluminum metal matrix composites (AMMCs) • Experimental • Mechanical Alloying • Microwave Sintering • Hot Extrusion • Results • Conclusions • Acknowledgements
Motivation of the work Reference: http://image.slidesharecdn.com/ocinnovationscompositesfeb2014rev6-140417023855-phpapp01/95/enhancing-the-performance-of-key-composite-applications-through-new-glass-reinforcements-8-638.jpg?cb=1397702464
AMMCs in automotive industry Reference: http://www.slideshare.net/Masum555/textile-composite
What is composite…? + = COMPOSITE MATRIX REINFORCEMENT A materials system composed of two or more physically distinct phases whose combination produces aggregate properties that are superior from those of its constituents.
What is a real Composite…? = NEW MATERIAL PROPERTIES A+B + MATERIAL 1 PROPERTIES A MATERIAL 2 PROPERTIES B 1 + 1 = 2 MATERIAL ALLOY + = NEW MATERIAL PROPERTIES A+B + ADDED VALUE! MATERIAL 1 PROPERTIES A MATERIAL 2 PROPERTIES B 1 + 1 > 2 COMPOSITE MATERIAL
POLYMERS FIBRES METALS POLYMER MATRIX COMPOSITES FIBRE REINFORCED COMPOSITES METAL MATRIX COMPOSITES NANO- MATERIALS CERAMICS NANO- COMPOSITES CERAMIC COMPOSITES Family of Composites FAMILY OF COMPOSITES
Global Aluminum Market On average, the light vehicles in the US and the EU member countries contain 148 kg of Al. Primary Al consumption by Industries, 2015 • Consumption of Al is increasing in automobile industry. • The global consumption of Al is forecast to rise by 7% per year between 2011 and 2016, reaching approximately 61 million tones in 2016. • Japanese cars, Al accounts for 8% of the total weight. Reference: http://www.rusal.ru/en/aluminium/key_markets/
Back Ground on MMC’s Reference: http://www.transparencymarketresearch.com/pressrelease/aluminum-alloys-market.htm Reference: http://www.grandviewresearch.com/industry-analysis/metal-matrix-composites-mmc-market
Why Al-MMC’s Composites? • Salient features of Al-MMCs when compared to Al-alloys are: • Higher stiffness and strength • Lower density (weight) • Enhanced mechanical properties • Controllable thermal properties (heat control/management) • Improved abrasion and wear resistance • Enhanced electrical performance Reference: file:///C:/Users/Lenovo/Downloads/MMC%20for%20Automotive%20industry.pdf
Experimental overview Pure Aluminum Cold Compaction Microwave Sintering Hot Extrusion High Energy Ball Milling Nano Si3N4 powders Characterization Mechanical & Electrical Microhardness Compression Ele. Conductivity Structural XRD SEM • Physical • Density • Porosity
Synthesis of Al-Si3N4 Al-0.3Si3N4 Al-0.6Si3N4 Al-0.9Si3N4 Al-1.2Si3N4 • Mechanical Alloying • Microwave Sintering Technique • Hot Extrusion
Mechanical alloying to final cylindrical billets PM 400 RPM—200 Time—120 m No Binders 100 ton Hydraulic Press Die Compacted Billets Diameter-35mm Height- ~40 mm Pressure – 50 ton
Microwave Sintering Process Microwave sintering is a promising technology for faster, cheapest and most environmental-friendly processing of a wide variety of ceramics and composites. Internal heating, Rapid heating. Select heating, High heating efficiency Heating uniformity, Clean energy Rapid response and temperature control Good working and operating environment Benefits Microwave sintered Composites
Hot extrusion process Al-Si3N4 Composites • Soaked: 400°C for 60 min • Extruded at 350ºC • Extruded rod ф8 mm • Extrusion ratio = 20:1 • Lubricant--- Graphite Pure Al 0.3 SN 0.6 SN 0.9 SN 1.2 SN
XRD Analysis Si3N4 • A phase pure Al-Si3N4 nanocomposite has been synthesized.
SEM Analysis Pure Al Al-0.3SiN Al-0.6SiN Si3N4 Si3N4 Al-1.2SiN Al-0.9SiN Si3N4 Cluster Clusters • Si3N4 nanoparticles are incorporated in to aluminum matrix. • Some regions have agglomerates of Si3N4 due to high density of Si3N4 particles (3.44 g/cm3) than Al (2.7 g/cm3). • A rich interface between metal matrix and Si3N4 particles is achieved.
Microhardness • The microhardness of AMMCs increases with increase in vol.% of Si3N4 particles.
Compressive strength The compressive strength increases with the increase in Si3N4 contents. The compressive strength increases from 121.57 MPa to 294.79 MPa. This increase in compressive strength is due to dispersion hardening effect of occurrence of hard Si3N4 particles in the aluminum matrix
Electrical Conductivity • The electrical conductivity decreases by increasing the Si3N4 percent.
Conclusions • Novel Al-Si3N4 nanocomposites were synthesized using microwave sintering and subsequent hot extrusion process. • The XRD and SEM analyses confirm the formation of phase pure Al—Si3N4 nanocomposites containing different amount of reinforcement. • Microhardness of the composites enhances with increasing amount of Si3N4 used as reinforcement. • The compressive strength increases with increasing amount of Si3N4 . • Electrical conductivity decreases with respect to addition of vol.% of Si3N4 reinforcement nanoparticles (i.e. from 0% to 1.2%).
Future Work • More detailed study on composition, microstructure and property relationship of developed Al-Si3N4 nanocomposites containing different amount of reinforcement. • Measurement of thermal conductivity of synthesized composites. • Study the tensile properties of the developed Al-Si3N4 nanocomposites. • Wear behavior of Al-Si3N4 having different amount of reinforcement at room temperature. • Corrosion behavior of developed Al-Si3N4 composites in saline water.
Acknowledgements • The presenter (Dr. R. A. Shakoor ) and research group members (Dr. Adel Mohamed, Dr. Penchal Reddy. M and Ms. Fareeha Ubaid) are grateful to Qatar Foundation (QF) for providing financial support through its National Research Fund (QNRF) from NPRP-7-159-2-076 research grant. • Dr. Manoj Gupta, National University of Singapore (NUS) for providing an opportunity to access his lab. facilities. • We are grateful to organizers of Ceramics 2016 conference for giving us this opportunity to share our latest research.