Showing 3 results for Tib2
M. F. Najafabadi and M. A. Golozar,
Volume 23, Issue 1 (7-2004)
Abstract
In this research work, the possibility of semi industrial production of Al-TiB2 and Al-ZrB2 composites, using reactive slag in a flame furnace have been investigated. For this purpose, commercial pure aluminum and powder mixture of TiO2 (ZrO2) , KBF4 and Na3AlF6 were used. The results showed that using a proper ratio of slag forming materials as well as proper amounts of the above-mentioned compounds make it possible to produce good quality Al-TiB2 and Al-ZrB2 compounds employing the conventional melting equipment such as a flame furnace.
E. Rostamizadeh, F. Ashrafizadeh , M. H. Abbasi,
Volume 34, Issue 2 (7-2015)
Abstract
this study, MoSi2-TiB2 nanocomposites with 10 and 20 wt.% of TiB2 were synthesized by mechanical alloying through two different methods. In the first method, elemental powders of molybdenum, silicon, titanium and boron were milled together for 60 hours. In the second method, MoSi2 was made by 30-hours milling of Mo and Si. Then, commercial TiB2 was added to the matrix and milling was continued for another 30 hours. Heat treatment was carried out on the resultant specimens at 1000˚C for 60 min. The effect of mechanical alloying on grain size and lattice strain was investigated by Williamson-Hall method using XRD patterns. The mechanical properties of the samples were determined by hardness test. It was found that TiB2 added to MoSi2 increased hardness considerably. Agglomeration process was carried out on the powders to be used in thermal spray process. The morphology and microstructure of the milled powders before and after agglomeration process were studied by SEM. The sphericity and particle size distribution of agglomerated particles were evaluated using Clemex software. The results showed that the nanocomposite powder produced by the first method had a higher quality for thermal spray process due to its higher hardness compared to the second one. It also had adequate particles sphericity.
B. Sharifian, G. H. Borhani, E. Mohammad Sharifi,
Volume 41, Issue 2 (11-2022)
Abstract
In this study, mechanically milled (MM) Al-24TiO2-20B2O3 powder in molten Al7075 matrix was used in order to fabricate in-situ TiB2 and Al2O3 reinforcements in Al7075 matrix. Differential thermal analysis (DTA) examination was adopted to find reaction temperature between milled Al, TiO2, and B2O3 powders. X-Ray Diffraction (XRD) patterns showed the existence of TiB2 and Al2O3 peaks (750 °C at Ar atmosphere) in MM powder. Scanning Electron Microscopy (SEM) results revealed the uniform distribution of TiO2 and B2O3 particles in the aluminum matrix. 6 wt.% MM powder was added to molten Al7075 at 750 °C. The molten Al7075/TiB2-Al2O3 composite was poured in copper mold. The stir casted composites were hot extruded at 465 °C with extrusion ratio of 6:1 and ram speed of 5 mm/s. The microstructures (optical microscopy and TEM) and mechanical properties (hardness and tensile testing) of samples were evaluated. TEM results showed that in-situ TiB2 nanoparticles were formed. The tensile strength of extruded Al7075/TiB2-Al2O3 composite was reached the value of 496 MPa. This result was around four times greater than that of the as cast Al7075 alloy.
