Abdulaziz S. Alaboodi

Structural Characterization and Mechanical Behavior of Al 6061 Nanostructured Matrix Reinforced with TiO2 Nanoparticles for Automotive Applications

The main aims of the present chapter are to: learn synthesis procedure of AA 6061‐x wt.% TiO 2 nanocomposites (x = 0, 2, 4, 6, 8, 10 and 12 wt.%) by mechanical alloying (MA); inves‐ tigate structural characterization of manufactured nanocomposite powders using X‐ray line profile analysis, scanning electron microscope (SEM) and transmission electron microscope (TEM); examine consolidation method and mechanical behavior in terms of sintered density, Vickers hardness and compressive stress‐strain behavior; study the improvement of ductility in nanocomposites; and simulate the mechanical behavior using ANSYS. Here, the synthesized nanocomposites via MA were consolidated using conventional uniaxial die compaction; then, the green compacts were sintered at differ‐ ent temperatures. TEM microstructures of as‐milled powder samples showed the matrix crystallite sizes ranging from 45 to 75 nm, which depended on the amount of reinforce‐ ment. A remarkable decrease in matrix powder particles size with the function of rein‐ forcement was observed due to the ceramic nano TiO 2 particles acted as milling agent. The sintered nanocomposites yielded maximum strength of 1.126 GPa. The study of tri‐ modeled composite and its mechanical behavior revealed the possibility of achieving improvements in ductility and toughness for nanocomposites. The simulated mechanical behavior results using finite element method were good agreement with experimental results.

Effect of Solvents on the Electronic Properties of Fullerene Based Systems:Molecular Modelling

Numerous efforts have been formed to explain the trends in room-temperature solubility of the fullerenes [2-4]. There are many different approaches to calculate and predict C60 solubility in organic solvents. Some of them are fully mechanistic [5-9], developed from the thermodynamical point of view; others are statistically based, with good correlation coefficients, but not transparent and complicated in interpretation [10-16].

Cold deformation of dezincification resistant yellow brass for plumbing applications

ABSTRACT In the present work, the room temperature deformation behavior of dezincification-resistant (DZR) brass was performed by varying strain rates (1 × 10−4 s−1, 0.55 × 10−3 s−1, 1 × 10−3 s−1, 0.55 × 10−2 s−1, 1 × 10−2 s−1) and percent cold works (15 to 65% with step of 10%). These parameters are important to plumbing parts of its forming. Room temperature deformation workability map was developed that provides the selection of safe deformation parameters without cracking. The as-received and deformed DZR brass samples were carefully characterized by various microscopes. The results revealed that more dislocations lines and twinning were observed through transmission electron microscope images as the strain rate (SR) increases which led to early failure of the sample before reaching the set height reduction. It was determined that more amount of strain hardening with designed height reduction was achieved at lower SR whereas less amount of strain hardening was achieved at higher SR due to strain mismatching phenomenon and various deformation mechanisms.