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 9/28/20161

Introduction o What are Composites? o Classification of Composites o Applications of Composites o Aluminum metal matrix composites (AMMCs) Experimental o Mechanical Alloying o Microwave Sintering o Hot Extrusion Results Conclusions Acknowledgements 9/28/20162 Outline of the Presentation

9/28/20163 Motivation of the work Reference: image.slidesharecdn.com/ocinnovationscompositesfeb2014rev phpapp01/95/enhancing-the-performance-of- key-composite-applications-through-new-glass-reinforcements jpg?cb=

9/28/20164 AMMCs in automotive industry Reference:

9/28/20165 What is composite…? A materials system composed of two or more physically distinct phases whose combination produces aggregate properties that are superior from those of its constituents. MATRIX REINFORCEMENT COMPOSITE + =

9/28/20166 What is a real Composite…? MATERIAL 1 PROPERTIES A MATERIAL 2 PROPERTIES B NEW MATERIAL PROPERTIES A+B + ADDED VALUE! > 2 COMPOSITE MATERIAL > 2 COMPOSITE MATERIAL + = MATERIAL 1 PROPERTIES A MATERIAL 2 PROPERTIES B NEW MATERIAL PROPERTIES A+B = 2 MATERIAL ALLOY = 2 MATERIAL ALLOY + =

9/28/20167 POLYMER MATRIX COMPOSITES POLYMERS CERAMICS CERAMIC COMPOSITES METALS METAL MATRIX COMPOSITES NANO- MATERIALS NANO- COMPOSITES FIBRES FIBRE REINFORCED COMPOSITES FAMILY OF COMPOSITES Family of Composites

9/28/20168 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 Japanese cars, Al accounts for 8% of the total weight. Primary Al consumption by Industries, 2015 On average, the light vehicles in the US and the EU member countries contain 148 kg of Al. Global Aluminum Market Reference:

9/28/20169 Back Ground on MMC’s Reference: Reference:

9/28/ 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 Why Al-MMC’s Composites? Reference: file:///C:/Users/Lenovo/Downloads/MMC%20for%20Automotive%20industry.pdf

Experimental overview 11 Pure Aluminum Nano Si 3 N 4 powders High Energy Ball Milling Hot Extrusion Microwave Sintering Cold Compaction Physical Density Porosity Physical Density Porosity Mechanical & Electrical Microhardness Compression Ele. Conductivity Mechanical & Electrical Microhardness Compression Ele. Conductivity Structural XRD SEM Structural XRD SEM

 Mechanical Alloying  Microwave Sintering Technique  Hot Extrusion Synthesis of Al-Si 3 N 4

Mechanical alloying to final cylindrical billets RPM—200 Time—120 m No Binders Diameter-35mm Height- ~40 mm Pressure – 50 ton Die 100 ton Hydraulic Press PM 400 Compacted Billets

9/28/ Microwave sintering is a promising technology for faster, cheapest and most environmental-friendly processing of a wide variety of ceramics and composites. Microwave sintered Composites Internal heating, Rapid heating. Select heating, High heating efficiency Heating uniformity, Clean energy Rapid response and temperature control Good working and operating environment Internal heating, Rapid heating. Select heating, High heating efficiency Heating uniformity, Clean energy Rapid response and temperature control Good working and operating environment Microwave Sintering Process

Soaked: 400°C for 60 min Extruded at 350ºC Extruded rod ф 8 mm Extrusion ratio = 20:1 Lubricant--- Graphite 15 Hot extrusion process Al-Si 3 N 4 Composites 0.3 SN 0.6 SN 0.9 SN 1.2 SN Pure Al

9/28/ XRD Analysis A phase pure Al-Si 3 N4 nanocomposite has been synthesized. Si3N4

9/28/ SEM Analysis Si 3 N 4 nanoparticles are incorporated in to aluminum matrix. Some regions have agglomerates of Si 3 N 4 due to high density of Si 3 N 4 particles (3.44 g/cm 3 ) than Al (2.7 g/cm3). A rich interface between metal matrix and Si 3 N 4 particles is achieved. Pure Al Clusters Al-0.3SiN Si3N4 Al-0.9SiN Si3N4 Cluster Al-0.6SiN Si3N4 Al-1.2SiN

18 The microhardness of AMMCs increases with increase in vol.% of Si 3 N 4 particles. Microhardness

9/28/ Compressive strength The compressive strength increases with the increase in Si 3 N 4 contents. The compressive strength increases from MPa to MPa. This increase in compressive strength is due to dispersion hardening effect of occurrence of hard Si 3 N 4 particles in the aluminum matrix

9/28/ Electrical Conductivity The electrical conductivity decreases by increasing the Si 3 N 4 percent.

9/28/ Conclusions Novel Al-Si 3 N 4 nanocomposites were synthesized using microwave sintering and subsequent hot extrusion process. The XRD and SEM analyses confirm the formation of phase pure Al—Si 3 N 4 nanocomposites containing different amount of reinforcement. Microhardness of the composites enhances with increasing amount of Si 3 N 4 used as reinforcement. The compressive strength increases with increasing amount of Si 3 N 4. Electrical conductivity decreases with respect to addition of vol.% of Si 3 N 4 reinforcement nanoparticles (i.e. from 0% to 1.2%).

More detailed study on composition, microstructure and property relationship of developed Al-Si 3 N 4 nanocomposites containing different amount of reinforcement. Measurement of thermal conductivity of synthesized composites. Study the tensile properties of the developed Al-Si 3 N 4 nanocomposites. Wear behavior of Al-Si 3 N 4 having different amount of reinforcement at room temperature. Corrosion behavior of developed Al-Si 3 N 4 composites in saline water. 9/28/ Future Work

9/28/ 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 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. Acknowledgements

9/28/ Thank you very much..