فهرس المقالات Titanium diboride

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  1 - Mechanically Activated Combustion Synthesis of B4C-TiB2 Nanocomposite Powder
  Maryam shojaie bahaabad
  Boron carbide is one of the hardest materials. The combustion method was used to synthesize B4C-TiB2 nanocomposite powder in a B2O3-Mg-TiO2-C system. An experimental study of the formation of B4C–TiB2 nanoparticles was conducted in the thermal explosion mode. A mi أکثر

  Boron carbide is one of the hardest materials. The combustion method was used to synthesize B4C-TiB2 nanocomposite powder in a B2O3-Mg-TiO2-C system. An experimental study of the formation of B4C–TiB2 nanoparticles was conducted in the thermal explosion mode. A mixture of B2O3:TiO2:Mg:C at a molecular ratio of 3:1:12:1 was chosen to obtain the B4C–TiB2. This powder mixture was milled for different times. The combustion reaction of powders milled for up to 12 h was done in an inert atmosphere at 900°C. The synthesized powders were characterized by X-Ray diffraction, Scanning and Transmission Electeron Microscopies (SEM and TEM). It was demonstrated that mechanical activation is a useful method for obtaining B4C and TiB2 powders simultaneously; without milling, the B4C composition did not form. B4C formed after 3 h of milling of the reactants. Crystallite size of products obtained from reactant powders milled for 6 and 12 hour was less than 100 nanometer. تفاصيل المقالة
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  2 - Production of Dispersed Ceramic Nano-Particles in Al Alloy Using Friction Stir Processing
  Amin Rabiezadeh Ahmad Afsari
  In this research, surface composite layers containing nano sized TiB2, Al2O3-TiB2, ZrO2 and CNT particles have been fabricated on Aluminum alloy substrates by friction stir processing. The effects of different processing variables such as number of passes and strengthen أکثر

  In this research, surface composite layers containing nano sized TiB2, Al2O3-TiB2, ZrO2 and CNT particles have been fabricated on Aluminum alloy substrates by friction stir processing. The effects of different processing variables such as number of passes and strengthening particle distribution, hardness, and wear properties of surface nanocomposite layers have been evaluated by electron microscopy, hardness, and wear test. Results showed that surface properties of aluminum alloy will be enhanced and the optimum conditions of properties which can be determined by comparing the effects of different parameters will be obtained. An increasein the number of passes up to four modifies microstructure and accordingly mechanical and wear properties were enhanced.Surface composite produced by FSP significantly improved the dry sliding wear resistance of the Al 6061 alloy by changing the wear mechanism. The FSPed sample with Al2O3-TiB2 particles had higher wear resistance in comparison with those with TiB2, ZrO2 and CNT. This enhancement is a consequent of better bonding between particles and aluminum matrix and higher microhardness. تفاصيل المقالة