aluminum wetting of carbon nano-tubes...aluminum wetting of carbon nano-tubes ayman ahmed, nathan...

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Carbon Nanotubes (CNTs) are known for their extraordinary strength and efficiency in heat conduction. In fact, CNTs are the stiffest and strongest known fibers to man. The high surface area and the perfect architecture of these CNTs are responsible for their amazing qualities. The ease of growth of these CNTs has led to some advanced research in this field. This project deals with infusing the great qualities of the CNTs into a very versatile metal such as aluminum. Aluminum is lighter than steel but lacks the rigidity of iron. Proper wetting of aluminum into CNTs would lead to a nano-composite which is extremely tough, durable and highly heat conductive. Hence, we look at the potential wetting properties of CNT forests decorated with metal nano-particles produced through laser ablation. Copper and nickel nano-particles being two metals that were tested. SETUP: Aluminum Wetting of Carbon Nano-tubes Ayman Ahmed, Nathan Hordy, Prof. Jean-Luc Meunier and Prof. Raynald Gauvin EXPERIMENTAL PROCEDURE: Substrate Cleaning 20 min with acetone in ultrasonic bath Heating Heat to 700° C for 30 min in Argon C 2 H 2 Injection 4 min C 2 H 2 injection (45 sccm) at 700° C Al melting on CNT 700/750/800° C for 0/15/30/60 mins Laser Ablation Decoration with Cu or Ni nano-particles CNT Growth 30 min growth at 700° C in Argon CONCLUSION: High quality CNTs can be created on Stainless Steel 316 at 700° C with 4 mins of C 2 H 2 injection and 30 mins growth time. Cu and Ni coating on the CNTs does not make a difference in terms of Al wettability. Al foil (97% Al) on CNT does not readily melt at its M.P. of 660.4° C due to the CNTs acting as a superb heat sink. At least 15 mins at 750° C is required for the proper melting process. Although Al foil falls off the CNTs, under SEM small clumps of Al are seen stuck onto the CNTs. EDS analysis reveals that these are primarily Aluminum oxide. These clumps reduce drastically in amount on 30 min of heating at 750°C and beyond. Further analysis needs to be done to see if a contact angle can be measured from the clumps to calculate wettability and also to observe the Al/CNT interface through electron microscopy. Denser metallic nano-particle decoration or full metallic coating around each CNT from PVD can also be possible alternatives. Special thanks to Mark McArthur RESULTS: CNTs survive even at high temperatures like 800° C and heating for 60 mins Al foil (small circles) always sticks to the SS 316 (big silver circles) after heating but it always falls off from the CNTs (big black circles). The heating causes the Al foil to shrink up and wrinkle After heating Although Al foil falls off, under the SEM, small clumps are seen at random places Using Energy-dispersive X-ray spectroscopy (EDS) these clumps are found to be Al and O being present in almost 1:1 ratio, suggesting there is a pure Al core surrounded by Al 2 O 3 POTENTIAL APPLICATIONS: Al based engine blocks Light car chassis Strong plane bodies More durable submarines Aerospace technology Power transmissions cables Excellent radiators and heat sinks Efficient cooling fins for electronics Brushes for commercial electric motors Robust weapons Body armour Sports equipment Alternative to steel/iron ...to name a few

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Page 1: Aluminum Wetting of Carbon Nano-tubes...Aluminum Wetting of Carbon Nano-tubes Ayman Ahmed, Nathan Hordy, Prof. Jean-Luc Meunier and Prof. Raynald Gauvin EXPERIMENTAL PROCEDURE: Substrate

Carbon Nanotubes (CNTs) are known for their extraordinary strength and efficiency in heat conduction. In fact, CNTs are the stiffest and strongest known fibers to man. The high surface area and the perfect architecture of these CNTs are responsible for their amazing qualities. The ease of growth of these CNTs has led to some advanced research in this field. This project deals with infusing the great qualities of the CNTs into a very versatile metal such as aluminum. Aluminum is lighter than steel but lacks the rigidity of iron. Proper wetting of aluminum into CNTs would lead to a nano-composite which is extremely tough, durable and highly heat conductive. Hence, we look at the potential wetting properties of CNT forests decorated with metal nano-particles produced through laser ablation. Copper and nickel nano-particles being two metals that were tested.

SETUP:

Aluminum Wetting of Carbon Nano-tubes

Ayman Ahmed, Nathan Hordy, Prof. Jean-Luc Meunier and Prof. Raynald Gauvin

EXPERIMENTAL PROCEDURE:

Substrate Cleaning 20 min with acetone

in ultrasonic bath

Heating Heat to 700° C

for 30 min in Argon

C2H2 Injection 4 min C2H2 injection (45 sccm) at 700° C

Al melting on CNT

700/750/800° C for 0/15/30/60 mins

Laser Ablation Decoration with Cu or Ni nano-particles

CNT Growth 30 min growth

at 700° C in Argon

CONCLUSION: High quality CNTs can be created on Stainless Steel 316 at 700° C with 4 mins of C2H2 injection and 30 mins

growth time. Cu and Ni coating on the CNTs does not make a difference in terms of Al wettability. Al foil (97% Al) on CNT does not readily melt at its M.P. of 660.4° C due to the CNTs acting as a superb heat sink. At least 15 mins at 750° C is required for the proper melting process. Although Al foil falls off the CNTs, under SEM small clumps of Al are seen stuck onto the CNTs. EDS analysis reveals that these are primarily Aluminum oxide. These clumps reduce drastically in amount on 30 min of heating at 750°C and beyond. Further analysis needs to be done to see if a contact angle can be measured from the clumps to calculate wettability and also to observe the Al/CNT interface through electron microscopy. Denser metallic nano-particle decoration or full metallic coating around each CNT from PVD can also be possible alternatives. Special thanks to Mark McArthur

RESULTS: CNTs survive even at high temperatures like

800° C and heating for 60 mins

Al foil (small circles) always sticks to the SS 316 (big silver circles) after heating but it always falls off from the CNTs (big black circles). The

heating causes the Al foil to shrink up and wrinkle

After heating

Although Al foil falls off, under the SEM, small clumps are seen at random places

Using Energy-dispersive X-ray spectroscopy (EDS) these clumps are found to be Al and O being present in almost 1:1 ratio, suggesting there is a pure Al core surrounded by Al2O3

POTENTIAL APPLICATIONS:

• Al based engine blocks

• Light car chassis

• Strong plane bodies

• More durable submarines

• Aerospace technology

• Power transmissions

cables

• Excellent radiators and

heat sinks

• Efficient cooling fins for

electronics

• Brushes for commercial

electric motors

• Robust weapons

• Body armour

• Sports equipment

• Alternative to steel/iron

...to name a few