Electro-Mechanical and Thermal Properties of Multiwalled Carbon Nanotube Reinforced Alumina Composites

2008 ◽  
Vol 368-372 ◽  
pp. 701-703 ◽  
Author(s):  
Kaleem Ahmad ◽  
Wei Pan ◽  
Chun Lei Wan
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Thermal Properties ◽  
Carbon Nanotube ◽  
Mechanical And Thermal Properties ◽  
Multiwalled Carbon ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Alumina Composites

Multi-walled carbon nanotube (MWNT) reinforced alumina composites with different MWNT contents (5 and 10 vol %) were fabricated by spark plasma sintering. The room temperature dc electrical conductivity, thermal conductivity, and mechanical properties were investigated. Results showed that the electrical conductivity has improved around twelve orders of magnitude by addition of 5 vol% of MWNT. The fracture toughness changed from 3.2 to 4.4 MPa m1/2 with 39% improvement over monolithic Al2O3. The thermal conductivity decreased with increase of MWNT contents. The low values of thermal conductivity suggest that interfacial thermal barrier play an important role in determining these properties. MWNT can be used to improve concurrently electrical, mechanical properties of Al2O3 but with lower values of thermal properties.

Improving mechanical and thermal properties of graphite–aluminium composite using Si, SiC and eggshell particles

2019 ◽  
Vol 54 (17) ◽  
pp. 2365-2376 ◽  
Author(s):  
MO Durowoju ◽  
TB Asafa ◽  
ER Sadiku ◽  
S Diouf ◽  
MB Shongwe ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Thermal Expansion ◽  
Thermal Properties ◽  
Relative Density ◽  
Coefficient Of Thermal Expansion ◽  
Mechanical And Thermal Properties ◽  
Sem Images ◽  
Plasma Sintering ◽  
Low Thermal Expansion ◽  
Spark Plasma

Graphite–aluminium (Gr–Al) composites are being used for diverse engineering applications because of their light weight, good electrical conductivity and thermal properties. However, their applications are limited by high coefficient of thermal expansion and low microhardness values which can be enhanced by adding cheap and efficient fillers. This paper reports the effect of addition of eggshell (ES) particles on the properties of sintered Gr–Al-based composites. Five different composites (Gr–Al, Gr–Al  +  20 wt.%Si, Gr–Al + 20 wt.%SiC, Gr–Al + 20Si wt.% + 20 wt.%ES and Gr–Al + 20SiC wt.% + 20 wt.%ES) were sintered at a temperature of 540 ℃, holding time of 10 min, heating rate of 52 ℃/min and pressure of 50 MPa using spark plasma sintering system. The sintered samples were characterized based on morphology, microhardness, relative density, coefficient of thermal expansion and electrical conductivity. Based on SEM images, graphite particles of flake-like structure were largely undeformed while Al particles were smaller, round and irregular in shape and fairly uniformly distributed in the composites. The microhardness value of sintered Gr–Al + 20 wt.%SiC + 20 wt.%ES composite was 39.55 HV compared to 30.46 HV for Gr–Al, the least of the samples. The Gr–Al + 20 wt.%SiC + 20 wt.%ES composite also has a very low thermal expansion coefficient (0.98 × 10−5/K) but lowest electrical conductivity at temperature beyond 150 ℃. Highest densification and minimum relative density (94%) were obtained in Gr–Al + 20 wt.%Si + 20 wt.%ES composite. These enhanced performances are largely due to the incorporation of ES particles. This study therefore demonstrated that ESs particles enhanced microhardness and lowered thermal expansion of Gr–Al-based composites which have promising applications in industries especially for thermal management.

scholarly journals Multiwalled carbon nanotube monoliths prepared by spark plasma sintering (SPS) and their mechanical properties

2009 ◽  
Vol 19 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Motohiro Uo ◽  
Tomoka Hasegawa ◽  
Tsukasa Akasaka ◽  
Isao Tanaka ◽  
Fuminori Munekane ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotube ◽  
Spark Plasma Sintering ◽  
Multiwalled Carbon Nanotube ◽  
Multiwalled Carbon ◽  
Plasma Sintering ◽  
Spark Plasma

Effect of Coating on the Thermal Conductivities of Diamond/Cu Composites Prepared by Spark Plasma Sintering (SPS)

2014 ◽  
Vol 722 ◽  
pp. 25-29 ◽  
Author(s):  
Q.L. Che ◽  
X.K. Chen ◽  
Y.Q. Ji ◽  
Y.W. Li ◽  
L.X. Wang ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Theoretical Prediction ◽  
Volume Fraction ◽  
Interface Reaction ◽  
Copper Matrix ◽  
Bonding Force ◽  
Ti Alloys ◽  
Plasma Sintering ◽  
Spark Plasma

The carbide forming is proposed to improve interfacial bonding between diamond particles and copper-matrix for diamond/copper composites. The volume fraction of diamond and minor titanium are optimized. The microstructures, thermal properties, interface reaction production and its effect of minor titanium on the properties of the composites are investigated. The results show that the bonding force and thermal conductivity of the diamond/Cu-Ti alloys composites is much weaker and lower than that of the coated-diamond/Cu. the thermal conductivity of coated-60 vol. % diamond/Cu composites is 618 W/m K which is 80 % of the theoretical prediction value. The high thermal conductivity has been achieved by forming the titanium carbide at diamond/copper interface to gain a good interface.

scholarly journals Compressive strength and thermal properties of spark plasma sintered Al-Al2O3 nanocomposite

2018 ◽  
Vol 50 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Nouari Saheb ◽  
Muhammad Khan
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Yield Strength ◽  
Coefficient Of Thermal Expansion ◽  
Testing Machine ◽  
Thermal Constant ◽  
Compressive Properties ◽  
Plasma Sintering ◽  
Spark Plasma

In this work, compressive and thermal properties of aluminum, milled aluminum, and Al-10Al2O3 composite processed via ball milling (BM) and spark plasma sintering (SPS) were investigated. The microstructural features of powders and sintered samples were characterized using optical and scanning electron microscopy. A universal testing machine was used to determine the compressive properties of the consolidated samples. The thermal conductivity and coefficient of thermal expansion of the developed materials were characterized using a hot disc thermal constant analyzer and a dilatometer, respectively. The Al-10Al2O3 composite possessed hardness of 1309.7 MPa, yield strength of 311.4 MPa, and compressive strength of 432.87 MPa compared to hardness of 326.3 MPa, yield strength of 74.33 MPa, and compressive strength of 204.43 MPa for aluminum. The Al-10Al2O3 composite had thermal conductivity value 81.42 W/mK compared to value of 198.09 W/mK for aluminum. In the temperature range from 373 K to 723 K, the composite had lower CTEs ranging from 10 ? 10?6 to 22 ? 10?6/K compared to 20 ? 10?6 to 30 ? 10?6/K for aluminum.

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