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The composite coating of a titanium carbide aluminide–alumina-iron composite was synthesized by centrifugal-assisted self-propagating high-temperature synthesis (SHS). The in situ TiC–Al2O3–Fe with intermetallic phases of titanium aluminide (TiAl/Ti3Al) possesses excellent metallurgical properties. This composite was produced from compacted titanium (Ti) and carbon (C) powders in the form of pellets embedded in a tube, which were exposed to very high temperature generated by the thermite Fe2O3 and Al reaction. The process took place in a graphite–steel tube mounted in a centrifugal accelerator machine purposely developed for this function. Functionally graded coating was produced under the centrifugal acceleration field and the product of the thermite reaction (Al2O3 and Fe) infiltrated the TiC pellet and to create a strong, titanium aluminide intermetallic layer. The centrifugal force significantly enhanced both metallurgical alloying and mechanical interlocking between different sample layers during product formation. The purpose of the research addresses the applications of local reinforcement of the ceramic-lined tubes.

The determination of the myocardium's tissue properties is important in constructing functional finite element (FE) models of the human heart. To obtain accurate properties especially for functional modeling of a heart, tissue properties have to be determined in vivo. At present, there are only few in vivo methods that can be applied to characterize the internal myocardium tissue mechanics. This work introduced and evaluated an FE inverse method to determine the myocardial tissue compressibility. Specifically, it combined an inverse FE method with the experimentally-measured left ventricular (LV) internal cavity pressure and volume versus time curves. Results indicated that the FE inverse method showed good correlation between LV repolarization and the variations in the myocardium tissue bulk modulus K (K = 1/compressibility), as well as provided an ability to describe in vivo human myocardium material behavior. The myocardium bulk modulus can be effectively used as a diagnostic tool of the heart ejection fraction. The model developed is proved to be robust and efficient. It offers a new perspective and means to the study of living-myocardium tissue properties, as it shows the variation of the bulk modulus throughout the cardiac cycle.

A modified smoothed particle hydrodynamic (MSPH) computational technique was utilized to simulate molten particle motion and infiltration speed on multi-scale analysis levels. The radial velocity and velocity gradient of molten alumina, iron infiltration in the TiC product and solidification rate, were predicted during centrifugal self-propagating high-temperature synthesis (SHS) simulation, which assisted the coating process by MSPH. The effects of particle size and temperature on infiltration and solidification of iron and alumina were mainly investigated. The obtained results were validated with experimental microstructure evidence. The simulation model successfully describes the magnitude of iron and alumina diffusion in a centrifugal thermite SHS and Ti + C hybrid reaction under centrifugal acceleration.

The purpose of this article is to synthesize a Ti-C system under a known cooling rate by applying a secondary hybrid system in the form of semi-reacted titanium carbide. The synthesis reaction is performed in a hot, inert, shielded crucible. The portions of reacting and interacting materials are determined using the Rietveld phase quantification method. The product microstructure is studied, and the nanomechanical properties are measured via a nanoindentation technique. The experimental results revealed that the reaction behavior and mechanical properties of Ti+C elemental powder were initiated at a particular temperature level. At 2610°C, the titanium carbide phase formed 14% of the compound composition, with 65 GPa Young’s modulus and 563 MPa hardness.

This paper presents modeling results for fatigue crack growths of a semi-elliptical surface crack in a V-shaped notched round bar under uniform cyclic tension. All the analyses were carried out by using a software package featuring the boundary element method. The J-integral technique was used to compute the stress intensity factors (SIFs), and the NASGRO crack growth rate was chosen to simulate the fatigue crack growths. Mechanical and fracture properties of AZ-6A-T5 magnesium alloy were used for our analysis. Crack shape evolutions for different crack aspect ratios and the corresponding stress intensity factors may be correlated to study the behavior of crack growths. An unstable crack growth was observed when the evolving crack aspect ratio was between 0.6 and 0.7. Careful consideration should be taken if the cylinder contains a defect which has a straight shape on the crack front or a smaller crack aspect ratio.

: Thin-walled square columns are generally used as energy absorber in various applications due to their ease of fabrication and installation, high energy absorption capacity in terms of progressive plastic deformation and long stroke. However, the main drawback of a standard square column is the high initial peak force. An ellipsoidal bulge base is proposed to overcome this shortcoming and at the same time to improve the crush performance. Static axial crushing were performed by finite element analysis to determine the initial peak force (IPF), crush force efficiency (CFE) and plastic specific energy absorption (SEA) of columns having ellipsoidal bulge bases with various thicknesses. It was found that the bulge base significantly enhanced the column crush performance as well as the deformation characteristics. A comparison with the plain square column was carried out and it was found that the bulge base reduced the initial peak force and increased the crush force efficiency. A simple analytical approach is proposed to predict the reduction of initial peak force with the use of this trigger mechanism.