Plasma-Assisted Rapid Sintering of Nanotitania Powders

ABSTRACTThe concept of 'hybrid heating with microwave (MW) energy at 2.45 GHZ.'for ultra rapid sintering of alumina is being introduced. This technique is a combination of MW - materual interaction as well as conventional radiant/conduction mechanisms, and facilitates the attainment of perhaps, the highest possible heating rates in a multimode MW cavity at 2.45 GJZz. (1500ºC in 120 sees.). Rapid sintering of pure.undoped alumina with this novel techniQue culminates in uniform, homogeneous microstructures and mechanical property enhancements vis-a-vis conventional fast firing.The role of green microstructure (particle size) on MW(hybrid) heating and processing variables (temperature, time) on the MW (hybrid) heating phenomena vs. conventional fast firing were investigated. Hybrid heated samples showed accelerated densification with comparable grain sizes when compared with the conventionally fast fired samples. The effectof particle size on the microwave (hybrid) heating phenomena was found to be analogous to conventional sintering.

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Enhancement of Mechanical Properties by Reinforcing Magnesium With Ni-Coated Carbon Nanotubes

Volume 12: Processing and Engineering Applications of Novel Materials ◽

10.1115/imece2010-38576 ◽

2010 ◽

Author(s):

M. H. Nai ◽

C. S. Goh ◽

S. M. L. Nai ◽

J. Wei ◽

M. Gupta

Keyword(s):

Carbon Nanotubes ◽

Load Transfer ◽

Matrix Material ◽

Strength Based ◽

The Matrix ◽

Rapid Sintering ◽

Reinforcing Material ◽

Coated Carbon ◽

Strength And Ductility ◽

Walled Cnts

In this study, carbon nanotubes (CNTs) are coated with nickel (Ni) to improve the wettability of the CNT surface and metal matrix, and allow an effective load transfer from the matrix to nanotubes. Pure magnesium is used as the matrix material and different weight percentages of Ni-coated multi-walled CNTs are incorporated as the reinforcing material. The nanocomposite materials are synthesized using the powder metallurgy route followed by microwave assisted rapid sintering. Mechanical property characterizations reveal an improvement of 0.2% yield strength, ultimate tensile strength and ductility with the addition of Ni-CNTs. As such, Ni-coated CNTs can be used as a reinforcement in magnesium to improve the formability of the material for light-weight, strength-based applications.

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The Effect of Microwave Sintering Time to PM Aluminum Alloys

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.754-755.240 ◽

2015 ◽

Vol 754-755 ◽

pp. 240-244

Author(s):

M.N. Derman ◽

Syaza Nabilla Mohd Suhaimi ◽

Zuraidawani Che Daud

Keyword(s):

Microwave Sintering ◽

Microwave Oven ◽

Solid Particles ◽

Binding Reaction ◽

Aluminium Powder ◽

Sintering Time ◽

Conventional Sintering ◽

Rapid Sintering ◽

Powder Particles ◽

Solid Liquid

Microwave sintering is new sintering technology method to produce Al alloys. The advantages of this method because of very short sintering time and less production cost compare to conventional sintering. However, the main problems in microwave sintering are required to be controlled sintering time due to rapid sintering mechanism. Therefore the effect of microwave sintering time to PM Aluminium will be studied. The compacted and sintered aluminium powder is placed in a microwave oven at a different period of 5 minutes, 10 minutes, 15 minutes and 20 minutes. Compression of 150 MPa is applied on aluminium powder to form pellets. Palette is shaped to 1cm in diameter and weighs 1g. SiC is placed together with aluminium samples in the microwave for the purpose of absorbing electromagnetic energy and is converted to heat. Results of different period sintering of aluminium pallet production altered physical properties of each sample. For a rapid sintering time, aluminium pallet does not show any binding reaction between powder particles. Whereas, for long microwave sintering period, solid particles phase change into solid-liquid phase caused by the movement and the formation of bonds between particles. Hence, this will be affecting the mechanical properties of the sample material.

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Properties of lightweight aggregate produced by rapid sintering of incinerator bottom ash

Resources Conservation and Recycling ◽

10.1016/j.resconrec.2004.05.004 ◽

2005 ◽

Vol 43 (2) ◽

pp. 147-162 ◽

Cited By ~ 143

Author(s):

C.R. Cheeseman ◽

A. Makinde ◽

S. Bethanis

Keyword(s):

Bottom Ash ◽

Lightweight Aggregate ◽

Rapid Sintering

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