Characterization of Al₂O₃ in High-Strength Mo Alloy Sheets by High-Resolution Transmission Electron Microscopy

Abstract

A novel type of alumina (Al2O3)-doped molybdenum (Mo) alloy sheet was prepared by a hydrothermal method and a subsequent powder metallurgy process. Then the characterization of α-Al2O3 was investigated using high-resolution transmission electron microscopy as the research focus. The tensile strength of the Al2O3-doped Mo sheet is 43-85% higher than that of the pure Mo sheet, a very obvious reinforcement effect. The sub-micron and nanometer-scale Al2O3 particles can increase the recrystallization temperature by hindering grain boundary migration and improve the tensile strength by effectively blocking the motion of the dislocations. The Al2O3 particles have a good bond with the Mo matrix and there exists an amorphous transition layer at the interface between Al2O3 particles and the Mo matrix in the as-rolled sheet. The sub-structure of α-Al2O3 is characterized by a number of nanograins in the $\left[ {2\bar{2}1} \right]$ direction. Lastly, a new computer-based method for indexing diffraction patterns of the hexagonal system is introduced, with 16 types of diffraction patterns of α-Al2O3 indexed.

Analytical Assessment of (Al2O3–Ag/H2O) Hybrid Nanofluid Influenced by Induced Magnetic Field for Second Law Analysis with Mixed Convection, Viscous Dissipation and Heat Generation

“…However, Al 2 O 3 possesses small fracture resistance and is flammable, so its use as a structural material is hindered. While metallic nanoparticles possess unique optoelectrical properties, are inflammable as well as high thermal and electrical conductivities [18][19][20]. Therefore, Al 2 O 3 -Ag/H 2 O is studied in present work.…”

Study on the erosion of Mo/ZrO2 alloys in glass melting process

“…As can be observed from Figure 2, with the increase of adding amount, the grain of alloy is reduced, which will influence the performance of the electrode. Therefore, the alloy prepared through using the new method has better distribution and small grain size, and the second phase particle size is only 200 nanometers as shown in the figure [17][18][19][20][21][22][23].…”

Investigation of the Microstructure and Mechanical Properties of Copper-Graphite Composites Reinforced with Single-Crystal α-Al2O3 Fibres by Hot Isostatic Pressing

“…When a dislocation moves forward and meets a hard Al 2 O 3 particle, it only moves around the particle, thus leaving a dislocation loop. This process requires energy; thus, the composites exhibit greater strength than the pure Cu [7]. Figure 7c presents the morphology of the composite in other regions, and Figure 7d shows the energy spectrum corresponding to point 2.…”

“…In addition to these materials, alumina (Al 2 O 3 ) is one of the most important ceramic reinforcements that has relatively high melting (2054 °C) and boiling points (2980 °C), ultrahigh thermal stability, and mechanical strength. Addition of fine Al 2 O 3 particles into the copper matrix can not only improve the hardness of this material, but also reduces the grain growth rate even at the temperatures approaching the melting point of the copper matrix [6,7]. Therefore, these kinds of composites are widely utilized in electronics, automobile, and aerospace fields as electrical contact materials, rocket thrusters, and components in aircraft engines, as well as in other applications [8,9].…”