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A more accurate kinematic model is extended in this work for vibrational analysis of a nanocomposite plate reinforced with graphene origami subjected to mechanical and thermal loading. The stretching part of transverse deflection is included in the kinematic relations in addition to the shear and bending components to arrive at a general formulation. The Hamiltonian procedure is extended to derive the governing equations of motion. The parametric results are obtained using the analytical method for investigating the impact of graphene origami reinforcement such as foldability and content as well as geometric parameters on the natural frequency responses. The results of this work can be used for the design of optimized structures and systems with high stiffness and low density applicable in multi-field loading conditions. As a novel conclusion, one can conclude that accounting thickness stretching leads to a decrease in natural frequencies because of more deformability and consequently a decrease in structural stiffness of stretchable plate.

Creep experiments were conducted on Cu–8.5 at.% Al alloy in the intermediate temperature range, 673–873 K, corresponding to 0.46–0.72 T_m, where T_m is the absolute melting temperature. The present analysis reveals the presence of two distinct deformation regions (climb and viscous glide) in the plot of log versus log σ. The implications of these results on the transition from power-law to exponential creep regime are examined. The results indicated that the rate-controlling mechanism for creep is the obstacle-controlled dislocation glide. A phenomenological model is proposed, which assumes that cell boundaries with sub-grains act as sources and obstacles to gliding dislocations.

Reducing the viscosity of liquid suspensions is vital in science and engineering. This paper explores the physical mechanism for the viscosity reduction method in liquid suspension by pulsed electric or magnetic field. The key is that the maximum volume fraction to be available for the suspended particles in the suspension increases with the particle size and the polydispersity in the particle size distribution. Positive experimental results with various liquid suspensions indicate that this method, developed from the basic mechanism of viscosity, is universal and powerful for all liquid suspensions with broad applications.

A method has been described for tracking material interface in a 3-Dim, rectangular-grid, time-dependent, Eulerian hydrodynamics code. The accuracy is crucial to the overall accuracy of the simulations. A 2^nd order accuracy interface reconstruction method based on the Youngs' scheme has been implemented in our new dynamic FEM code. The method is applicable to the type of code in which the layout of materials is described solely by the volume fraction of the various materials in each computational cell. The volume fraction distribution is used to construct a plane interface in each mixed cell. The position of interface determines the flow across cell sides and hence enables volume fractions to be updated to the next time level. In this paper, the 2^nd order accuracy method has been compared with the new 1^st order accuracy method which we recently implemented based on the SLIC (Simple Line Interface Calculation).

Effect of deformation induced transformation (DIT) process on ferrite grain size and ferrite transformation volume fraction in the refractory low alloy steel 12Cr1MoV by controlled rolling and controlled cooling technology were experimentally studied. Simulation experiments of hot deformation were carried out with the Gleeble-1500 system. Single-pass and multi-pass hot rolling process with different deformation temperature, deformation reduction, strain rate and cooling rate were performed separately. The ferrite grain size decreased and the ferrite volume fraction increased with decreasing deformation temperature, and the extra-fine ferrite grain about 1.01µm was obtained when the deformation temperature reached 780°C. Higher deformation reduction resulted finer ferrite grain size and higher ferrite volume fraction. Both the ferrite grain size and ferrite volume fraction decreased with increasing strain rate. The ferrite grain size decreased but the ferrite volume fraction didn't change much when the cooling rate increased. The grain size and the ferrite volume fraction were improved more by three-passes than two-passes rolling. The mechanism of grain refinement by DIT was discussed.

In this paper, the thermoelastic transient behavior of a clamped circular plate composed of functionally graded material (FGM) is investigated. The material properties of the FGM circular plate are assumed to vary through the plate thickness according to a power law distribution of the volume fraction of constituent materials, except Poisson's ratio, which is assumed as constant. Based on the von Karman equation and classical theory of thin plates, the equation of motion for the FGM circular plate is derived by the Hamilton principle. The nonlinear governing equation is solved by the Galerkin method, along with Newmark's integration method, in an iterative manner. Numerical results reveal that the functional gradient index, ratio of thickness to radius, thermal and mechanical loads have significant effect on the thermoelastic transient behavior of the clamped FGM circular plate. The result presented herein may be used as a reference for solving other transient coupled problems of thermoelasticity.

Composite nanobeams with carbon nanotube (CNT) reinforcement are crucial components in various applications due to their unique mechanical and thermal properties. The present work investigates the frequency–aspect ratio relationship in composite nanobeams with CNT reinforcement, particularly under varying temperatures, magnetic field strengths, and Winkler elastic stiffnesses. The non-dimensional frequency variation with aspect ratio, influenced by temperature differences, reveals distinct behavior patterns. The introduction of a magnetic field alters frequency characteristics, with uniform distribution (UD) nanobeams displaying higher frequencies. The impact of Winkler elastic stiffness, temperature differences, and magnetic field strengths on frequency elucidates differing responses between UD, $X$-type distribution (XD), and $V$-type distribution (VD) nanobeams. Nonlocal strain gradient theory proves essential in capturing dynamic characteristics influenced by CNT distribution. These findings shed light on the intricate dynamics of composite nanobeams, providing valuable insights for the design of future nano-devices employing CNT-reinforced composite beams as fundamental elements.

The quasi-static and dynamic compression responses and failure of fiber-reinforced syntactic foams were investigated. The role of fiber volume fraction on the compression response of syntactic foams was examined in terms of mechanical behavior and energy absorption under both quasi-static and dynamic conditions. Results showed that the mechanical behavior and energy absorption of the reinforced specimens increased with increasing fiber volume fraction. The syntactic foams exhibited distinct strain rate sensitivity; and their yield strength and elastic modulus increased by 41.1% and 85.1%, respectively, as strain rate increased from 0.0011 s${}^{\mathrm{\text{-1}}}$ to 1070 s${}^{\mathrm{\text{-1}}}$. The deformation and failure processes of the syntactic foams were also examined, and the underlying mechanisms were discussed.

A frictional sliding contact model is established for the anisotropic piezoelectric/piezomagnetic composites indented by a flat or circular stamp. The characteristic equation related to monoclinic anisotropic piezoelectric/piezomagnetic composites is of tenth-order. The stated problem is reduced to integral equations whose kernels present an unconventional singularity. Parametric studies reveal that both the volume fraction of the composites and the friction coefficient could significantly affect the tribological behaviors. Numerical results show that the surface quantities have a singularity or spike at the stamp edge, and that the magneto-electro coupling in piezoelectric/piezomagnetic composites does not exist in any single phase.

High-entropy alloy (HEA) is a type of alloy that exhibits high hardness, strength, good wear resistance, corrosion resistance, and versatility. Molecular dynamics simulations were conducted to illustrate the microscopic evolution of FeNiCrCoCu HEAs under varying twin boundary spacing (TBS). Compression revealed dislocation migration, variations in the quantity and radius of nanovoids, as well as grain boundary diffusion. With increasing strain, high-energy regions expand on the surface of the crystal, transitioning from an initially smooth state to uniform deformation accompanied by grain boundary diffusion, while dislocations occur within the crystal. The number and radius of observed nanovoids within the crystal increase. The mechanical characteristics of FeNiCrCoCu HEAs are influenced by the TBS size. The alloy demonstrates better mechanical properties when the TBS is 1.22nm. FeNiCrCoCu HEAs with a constant TBS showed improved mechanical characteristics when a greater number of grains ($N$) were present.

The objective of this paper is to study the effect of nanoparticles on Coefficient of Performance (COP) and thermal load of main components (generator, condenser, evaporator and absorber) of absorption refrigeration system using H₂O–LiBr. Al₂O₃ nanoparticles have been added into the H₂O–LiBr solution to make the binary nanofluid, and Polyvinyl Alcohol (PVA) has been used as a stabilizer. Experimentation part involves the preparation of nanofluid and tests on H₂O–LiBr and H₂O–LiBr with 0.05% Al₂O₃. The effect of nanoparticles on COP and thermal load of components has been studied by varying the operating temperatures (generator, condenser and absorber temperature) and volume fraction of nanoparticles. The results show that COP and thermal loads of system with nanoparticles at different operating temperatures are following the same trend as base fluid system. The COP of system with nanoparticles at each operating temperature is higher than base fluid system. The heat supplied to generator with nanoparticles is less than without nanoparticles while heat rejected in condenser and absorber with nanoparticles is higher than without nanoparticles at each operating temperature. The heat exchanged in evaporator with nanoparticles is also higher than that without nanoparticles at each operating temperature. We also obtained maximum COP with 0.2% volume fraction of nanoparticles.

The present paper reports abrasive wear behaviour of copper matrix composites reinforced with silicon carbide and silica particles. Copper – SiC (12%) and Copper-SiO₂ (9%) composites were prepared by powder metallurgical technique. Metallography, image analysis and hardness studies were carried out on copper composites. The abrasive wear experiments were carried out using pin on disc apparatus. The effect of sliding distance and load was studied on Copper – SiC (12%) and Copper-SiO₂ (9%) composites. The abrasive wear volume loss increased with sliding distance in both the composites although the magnitude of increase was different in each case. Copper – SiC (12%) composites exhibited relatively better abrasion resistance as compared to and Copper-SiO₂ (9%) composites. The abraded surfaces were observed under scanning electron microscope to study the morphology of abraded surfaces and operating wear mechanism. The analysis of wear debris particles was also carried out to substantiate the findings of the investigation.