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The purpose of this paper is to consider the static analysis of nanocomposite plates. Nanocomposites consist of a small amount of nanoscale reinforcements which can have an observable effect on the macroscale properties of the composites.

In the present study the reinforcements considered are non‐spherical, high aspect ratio fillers, in particular nanometer‐thin platelets (clays) and nanometer‐diameter cylinders (carbon nanotubes, CNTs). These plates are considered simply supported with a bi‐sinusoidal pressure applied at the top. These conditions allow the solving of the governing equations in a closed form. Four cases are investigated: a single layered plate with CNT reinforcements in elastomeric or thermoplastic polymers, a single layered plate with CNT reinforcements in a polymeric matrix embedding carbon fibers, a sandwich plate with external skins in aluminium alloy and an internal core in silicon foam filled with CNTs and a single layered plate with clay reinforcements in a polymeric matrix. A short review of the most important results in the literature is given to determine the elastic properties of the suggested nanocomposites which will be used in the proposed static analysis. The static response of the plates is obtained by using classical two‐dimensional models such as classical lamination theory (CLT) and first order shear deformation theory (FSDT), and an advanced mixed model based on the Carrera Unified Formulation (CUF) which makes use of a layer‐wise description for both displacement and transverse stress components.

The paper has two aims: to demonstrate that the use of classical theories, originally developed for traditional plates, is inappropriate to investigate the static response of nanocomposite plates and to quantify the beneficial effect of the nanoreinforcements in terms of static response (displacements and stresses).

In the literature these effects are usually given only in terms of elastic properties such as Young moduli, shear moduli and Poisson ratios, and not in terms of displacements and stresses.

Recently nanoparticles reinforced lead free solders are vastly developed in electronics packaging industry. Studies and investigations have been conducted to learn and investigate the types, properties, method, availability and importance of nanoparticles in this field.

Mechanical properties, melting temperature and microstructural conditions are taken into major considerations in any of the preparation on nanoparticles and being reviewed in this paper. Segregation of the types of nanoparticles being added together with their properties is summarized in this paper. High temperature reliability is crucial in providing a good viable solder and hence addition of nanoparticles have been seen to give a positive outcome in this particular property.

This paper reviews on the beneficial of the various nanoparticles addition in the solder. Briefed explanations and the factors are revealed in this review.

This paper reviews on the beneficial of the various nanoparticles addition in the solder.

The purpose of this paper is to identify if the implementation of ultrasonic vibration in laser engineered net shaping (LENS) process can help to reduce internal weaknesses such as porosity, coarse primary TiB whisker and heterogeneous distribution of TiB reinforcement in the LENS-fabricated TiB reinforced Ti matrix composites (TiB-TMC) parts.

An experimental investigation is performed to achieve the results for comparative studies under different fabrication conditions through quantitative data analysis. An approach of microstructural characterization and mechanical testing is conducted to obtain the output attributes. In addition, the theoretical analysis of the physics of ultrasonic vibration in the melting materials is presented to explain the influences of ultrasonic vibration on the microstructural evolution occurred in the part fabrication.

Because of the nonlinear effects of acoustic streaming and cavitation induced by ultrasonic vibration, porosity is significantly reduced and a relatively small variation of pore sizes is achieved. Ultrasonic vibration also causes the formation of smaller TiB whiskers that distribute along grain boundaries with a homogeneous dispersion. Additionally, a quasi-continuous network (QCN) microstructure is considerably finer than that produced by LENS process without ultrasonic vibration. The refinements of both reinforcing TiB whiskers and QCN microstructural grains further improve the microhardness of TiB-TMC parts.

The novel ultrasonic vibration-assisted (UV-A) LENS process of TiB-TMC is conducted in this work for the first time to improve the process performance and part quality.

The purpose of this paper is to examine the mechanical characteristics and optimization of wear parameters of hybrid (TiO₂ + Y₂O₃) nanoparticles with Al matrix using squeeze casting technique.

The hybrid aluminium matrix nanocomposites (HAMNCs) were fabricated with varying concentrations of titanium oxide (TiO₂) and yttrium oxide (Y₂O₃), from 2.5 to 10 Wt.% in 2.5 Wt.% increments. Dry sliding wear test variables were optimized using the Taguchi method.

The introduction of hybrid nanoparticles in the aluminium (Al) matrix was evenly distributed in contrast to the base matrix. HAMNC6 (5 Wt.% TiO₂ + 5 Wt.% Y₂O₃) reported the maximum enhancement in mechanical properties (tensile strength, flexural strength, impact strength and density) and decrease in porosity% and elongation% among other HAMNCs. The results showed that the optimal combination of parameters to achieve the lowest wear rate was A3B3C1, or 15 N load, 1.5 m/s sliding velocity and 200 m sliding distance. The sliding distance showed the greatest effect on the dry sliding wear rate of HAMNC6 followed by applied load and sliding velocity. The fractured surfaces of the tensile sample showed traces of cracking as well as substantial craters with fine dimples and the wear worn surfaces were caused by abrasion, cracks and delamination of HAMNC6.

Squeeze-cast Al-reinforced hybrid (TiO₂+Y₂O₃) nanoparticles have been investigated for their impact on mechanical properties and optimization of wear parameters.

The purpose of this paper is to investigate the effects of addition Co nanoparticles on the characteristic properties of Sn‐3.8Ag‐0.7Cu solder.

Cobalt (Co) nanoparticles were added to Sn‐Ag‐Cu solders by thoroughly blending various weight percentages (0‐2.0 wt%) of Co nanoparticles with near eutectic SAC387 solder paste. Blending was done mechanically for 30 min to ensure a homogeneous mixture. The paste mixture was then reflowed on a hot plate at 250°C for 45 s. The melting points of nanocomposite solder were determined by differential scanning calorimetry. Spreading rate of nanocomposite was calculated following the JIS Z3198‐3 standard. The wetting angle was measured after cross‐sectional metallographic preparation.

No significant change in melting point of the solder was observed as a result of Co nanoparticle addition. The wetting angles of the solder increased with the addition of nanoparticles, while the spreading rate decreased. Although the wetting angle increased, the values were still within the acceptable range. Scanning micrograph observations revealed that the as‐solidified microstructure of the composite solder was altered by the addition of Co nanoparticles. Microhardness of the solders slightly increased upon Co nanoparticles addition to SAC387.

The paper demonstrates that a simple process like paste mixing can be used to incorporate nanoparticles into solder.

The purpose of this paper is to propose a novel method to prepare pure Ti powder for 3D printing with tailorable particle size distribution.

The main procedures of the present method consist of gas state reaction to synthesize TiH₂ nanoparticles, agglomeration to obtain micronscale powder particles by spray drying, and densification of particle interior by heat treatment.

The prepared Ti powder has a specific bimodal particle size distribution in a range of small sizes, good sphericity and high flowability. Particularly, this new technique is capable of controlling powder purity and adjusting particle size.

To the best knowledge of the authors, the approach for preparing 3D printing metallic powders from nanoparticles has not been reported in the literature so far. This work provides a novel method that is particularly applicable to prepare 3D printing metallic powders which have small initial particle sizes and high reactivity in the air.

The main objective of this article is to develop a theoretical formulation for predicting the response of CNTs reinforced beam under multiple impactors with general boundary conditions, using first-order shear deformation beam theory.

The rule of mixtures is implemented to derive the material properties of the beam. The nonlinear Hertz contact law is applied for simulation between impactors and the surface of the beam. A combination of approaches includes energy method, Ritz method and generalized Lagrange equations are used to extract the matrix form of equations of motion. The time-domain solution is obtained using implementing the well-known Runge Kutta 4th order method.

After examining the accuracy of the present method, the effects of the number of impactors include one impactor, and three impactors in various CNTs volume fraction are studied for CNTs reinforced beam with clamped-clamped, clamped-free and simply supported boundary conditions under the low-velocity impact. The most important finding of this article is that contact force and beam indentation at the middle of the beam in the case of one impactor are greater than those reported in the case of three impactors.

This article fulfills an identified need to study how CNTs reinforced beam behaviour with general boundary conditions under multiple low-velocity impacts can be enabled.

This paper aims to provide a review on the process of additive manufacturing of ceramic materials, focusing on partial and full melting of ceramic powder by a high-energy laser beam without the use of binders.

Selective laser sintering or melting (SLS/SLM) techniques are first introduced, followed by analysis of results from silica (SiO₂), zirconia (ZrO₂) and ceramic-reinforced metal matrix composites processed by direct laser sintering and melting.

At the current state of technology, it is still a challenge to fabricate dense ceramic components directly using SLS/SLM. Critical challenges encountered during direct laser melting of ceramic will be discussed, including deposition of ceramic powder layer, interaction between laser and powder particles, dynamic melting and consolidation mechanism of the process and the presence of residual stresses in ceramics processed via SLS/SLM.

Despite the challenges, SLS/SLM still has the potential in fabrication of ceramics. Additional research is needed to understand and establish the optimal interaction between the laser beam and ceramic powder bed for full density part fabrication. Looking into the future, other melting-based techniques for ceramic and composites are presented, along with their potential applications.

The reliable performance of critical components working under extreme conditions is paramount to the safe operation of aircraft, and material selection is critical. Copper alloys are an obvious choice for such applications whenever a combination of transport, mechanical and tribological properties is required. However, low strength and hardness issues require development of new copper alloys and composites to improve service life and reliability. This study aims to investigate the effect of carbon nanotubes as reinforcement phase in copper-matrix composites.

The development of novel copper-based composites refined to the nanoscale was envisaged through mechanical milling of mixtures containing copper and carbon nanotubes (2 Wt.%). Milling took place in a planetary ball mill for times varying between 1 h and 16 h at 400 rpm. A ball-to-powder ratio of 20:1 and alumina vial and copper spheres were used under dry conditions or with addition of isopropyl alcohol. Scanning electron microscopy/energy dispersive spectroscopy, size distribution, Raman spectroscopy and X-ray diffraction were used to study the produced powders.

Attained results show that mechanical milling of the studied system produces nanostructured powders containing second-phase carbon nanotubes homogeneously distributed in the metallic matrix, together with severe copper grain refinement. This should correspond to increased residual microstresses, envisaging significant improvement of mechanical properties of the produced copper composites.

The novelty of the work resides in the use of carbon nanotubes for the reinforcement of copper, and on the systematic microstructural characterisation of the produced composites.

The purpose of this study, the tribological behaviors at different temperatures of aluminium matrix composites (AMCs) with different amounts of ZrO₂ added were investigated.

Aluminium graphite (A356/2 wt% graphite (solid lubricant)) composite powders prepared by adding four different amounts (3 wt%, 6 wt%, 9 wt% and 12 wt%) of Zirconia (ZrO₂) to the matrix were mechanically alloyed for 4 h. Wear tests were conducted at five different temperatures (20 °C, 100 °C, 180 °C, 260 °C and 340 °C) and for three different sliding distances (53 m, 72 m and 94 m) on the pin-on-disc type wear tester.

Results of the study showed that the highest hardness and density value were measured for 12% ZrO₂ added AMC material. Wear test results showed that weight loss increases with increasing temperature; weight loss decreases at all temperatures with the increasing amount of reinforcement in the matrix.

In this paper, the tribological properties of aluminium matrix composites produced by the mechanical alloying method by adding different amounts of ZrO₂ were determined by simulating the tribological properties at different loads and temperatures.