Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Silicon carbide

Modification of Prepared (Al 2024/Alumina/Mn) Composite by Laser Surface SiC Clad Layer

Marwa H. Juber; Amer H. Majeed; Mohammed S. Hamza; Thair A. Tawfiq

Engineering and Technology Journal, 2019, Volume 37, Issue 6A, Pages 201-206
DOI: 10.30684/etj.37.6A.3

The present work shows the cladding process of silicon carbide on the substrate of prepared composite (Al 2024/Alumina/Mn) by using a laser beam (pulsed Nd-YAG). To obtain the desired results, the best laser parameters were chosen. The parameters of the laser beam that have chief affected during the experiments in this work are peak power (1.9)kW, work frequency (8)Hz and pulse duration (5.3)ms, the preplaced powder technique favorite during a cladding process and the results in this work were proved by SEM, micro-hardness, EDS, and chemical corrosion tests. The results of the experimental work have shown that a micro-hardness increased about (28%) times for Aluminum/Alumina composite by silicon carbide cladding compared with the original value of micro-hardness, and thickness of the cladding layer was about (34μm). The resistance of corrosion was enhanced with about (35%) for the Aluminum/Alumina composite with SiC cladding.

Effect Nano-SiC Additives on Physical and Mechanical Properties of Bauxite Refractories Used in Oil Treatment Units

S.A. Zaidan; H. H. Jasim

Engineering and Technology Journal, 2017, Volume 35, Issue 10, Pages 992-998
DOI: 10.30684/etj.35.10A.5

Refractory mixtures were prepared from: bauxite raw materials, grog and Kaolin. Different weight percentage of micro-SiC (5, 10, 15 and 20 wt%) and nano-SiC (2.5,5,7.5 and 10 wt%) was added to bauxite mixture to improve the refractories characteristics to suit the lining of oil treatment units. Semi-dry pressing used to forming cylindrical specimens with load (7 ton) and 25 mm in diameter after mixing the powder with 10 wt% Sodium Silicate as a binder. The specimens dried at (110 oC) for (2 h) and fired at (1400 oC) with soaking time (2 h). During firing process, some of nano-SiC powder oxidants and transformed to SiO2 glass phase with increasing mullite phase. Therefore; the bonds with bauxite increases as a result glass phase generated and lead to decreasing the porosity and increasing the shrinkage, density and mechanical properties compared with micro-SiC additives.

Mechanical Strength of Silicon Carbide Bonded with Iraqi Clays

Abdul Mutalb Al Sheikh; Shihab Ahmed Zaidan Al- Juboori; Kassim S. Kassim

Engineering and Technology Journal, 2011, Volume 29, Issue 4, Pages 665-676

Two types of Iraqi clays (Kaolin and Bentonite) were used in bonding process
with different weight percentage (5%, 10%, 15%, 20%, and 25%) and with
different particle size from clays and silicon carbide.
The specimens were formed by using low biaxial pressing and two types of
internal lubricants (sodium silicate and the carbon paste) to increase the
specimen's cohesion. These specimens were sintered at various temperatures of
(1100°C, 1200°C, 1300°C, and 1400°C).
Increasing of clay percentage leads to decreasing the porosity. But it leads to
increase mechanical properties (compressive strength, diametrical strength and
bending strength ). Also, the effect of particle size on all properties is studied
together with sintering temperature. All mechanical properties (when bonded SiC
with bentonite) are higher than kaolin bonded SiC.