A clearer indication of the role of grain size in the optimization of the mechanical properties of TiB2 is provided by the fracture toughness as measured by the mode I critical stress intensity factor KIc. For fully dense specimens at room temperature, having a mass fraction of TiB2 ⩾ 98 %, KIc appears to have a maximum value for a mean grain size of 5 μm ⩽ g ⩽ 12 μm. The values may be influenced by three potentially significant factors: grain size, measurement method, and chemical impurity cont
What's tungsten powder? Tungsten powder Reduced with hydrogen in either a four tube muffle furnace (using tungsten dioxide as the raw material) or multi-tube furnace (using tungstenoxide). It has a particle size of 0.6 to 30 microns. It can be divided into medium, fine and coarse particles. It is determined using the national standard for impurities. The impurity content is determined by the national standard. Preparing tungsten powder using hydrogen reduction generally involves two stages.
Nanocrystalline cerium(IV) oxide (CeO2) powders were prepared by heating solutions of cerium(IV) salts in the presence of urea under hydrothermal conditions at 120° to 180°C. The effects of urea concentration and hydrothermal treatment temperature on the morphology and crystallite size of the synthesized particles were investigated. The synthesized particles were angular, ultrafine CeO2 with a cubic fluorite structure. Their crystallite size decreased from 20 to 10 nm with increasing urea concen
Rolling bearings codes describe the inner diameter, diameter series, size series, and type of the bearings, which are generally approximately five digits. The code is composed of basic code, article code, as well as front code.
