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The purpose of this paper is to analyse nanosecond pulsed laser ablation on both metallic materials and non-metallic materials; a comparison between metallic materials and non-metallic materials has also been included.

In this paper, FEM method has been used to calculate the result by means of the finite element method. Furthermore, all the analyses are based on thermal theories.

The paper presents a comparison of metallic and non-metallic materials. Besides, the effect of how laser parameter changes would influence the ablation depth has also been assessed.

All studies in this paper are based on classical thermal theories. Thermal theories are not applicable some times.

With the results of this paper, suggestions are made so that experiments and manufactures could be optimised and improved.

LAMINATED material from which non‐metallic bearings and gears are fabricated may consist of fabric or paper treated with a synthetic resin. In producing this material, rolls of paper or fabric are fed in at one end of an impregnator which imparts a coating of the resin varnish. The impregnated material is dried and cut into suitably sized sheets, which are placed in layers to form a block of the material. The block is next pressed by hydraulic pressure under heat. This causes the resin to soften and flow so that the paper or fabric laminations merge under the pressure, which is round about one ton per sq. in. As heating is continued, however, the resin sets and can no longer be affected by heat; the laminations lose their separate identity and the material becomes a homogeneous mass. Another type of material much in use consists of asbestos—which may or may not be in the form of asbestos cloth—likewise impregnated with synthetic resin.

This study aims to compare the friction and wear performance of commercial brake pads for four wheelers among metallic, semimetallic and non-asbestos organic (NAO) formulations to identify one with the right combination of properties for optimal performance.

Three commercially available brake pads for four-wheeler automotive applications were acquired. Samples were cut from the brake pads to study their physical and mechanical properties. The effects of friction and wear were analyzed using a pin-on-disk tribotester. Surface morphology on the worn-out surface of the brake pads was studied.

It was observed that the frictional properties remained stable and less fluctuating in the semimetallic and NAO pads, whereas the coefficient of friction of all the pads varied between 0.35 and 0.55. The wear rate of the metallic pads is less than that of NAO and semimetallic pads. The surface morphology studies revealed that the metallic pads contained more primary plateaus and smaller amounts of secondary plateaus compared to semimetallic and NAO pads, resulting in better wear resistance characteristics.

Because the market is flooded with various options for brake pad materials, it is imperative that the vehicle manufacturers choose the right pad material with great care not only to ensure the optimal functioning of the braking system but also passenger safety. Mechanical and tribological properties of brake pads contribute greatly to their effectiveness. There is a requirement to choose the proper material for a certain application that has a consistent friction coefficient and reduced wear.

Fluids management may be defined as the routeing and confinement of fluids, often under extremes of temperature, pressure and working environment. One of the most critical areas of this technology is the supply and transfer of liquids in aerospace fuel systems. Development of fluids management components for aerospace applications is driven by the requirement for total system integrity within the constraints of cost, space, mass, service conditions and material properties. Designers are challenged to produce novel solutions involving 3D simulation and modelling, finite element analysis and rapid prototyping. Simultaneous engineering is now an integral part of the process and designers must be aware of the latest manufacturing techniques and materials, both metallic and non‐metallic. Final design optimization is confirmed by prototype evaluation, followed by rigorous qualification testing. Explores design concepts and introduces some fluids management components in widespread use today. Reviews recent helicopter and non‐metallic material developments and discusses the future of the technology.

Metal green parts fabricated by indirect selective laser sintering (SLS) have lower mechanical properties, and thus, they cannot satisfy practical application. To enhance their performance, two polymer resins were compounded as a modified material to infiltrate into the metal parts by SLS.

The viscosity and glass-transition temperature were tested by a viscometer and differential scanning calorimetry, respectively. The microstructure and morphology of the interface of parts by polymer resin infiltrated were observed to be using scanning electron microscopy. The tensile strength of sample parts was tested, too. The temperature tolerances of two mass ratio polymer materials were tested and compared by thermo-gravimetric analysis (TGA).

Compared to those without being polymer material infiltrated, the results of test showed that the tensile strength of the metallic parts is enhanced obviously, about four times. In addition, the analysis of TGA showed that the resin of mass ratio of 2:1 can be endured up to 200° and can be used as infiltrating materials for metal parts.

Therefore, plastic injection mold and function part can be manufactured by this method.

This paper aims to introduce a novel approach to the fabrication of photoluminescent materials by coating rare earth aluminate luminescent materials on metallic substrates and a readily manufacturable light source with robust structure in the form of photoluminescent sphere (APS).

The clean and dried stainless steel sphere was sprayed with UH 2593, a white undercoat, the luminescent coating and the weather resistance coating in chronological order.

After adhered onto the stainless steel sphere, the peaks corresponding to the N-H stretching vibrations were changed. The intensity of free N-H stretching at 3,536 cm⁻¹ dramatically decreased and the peak of hydrogen-bonded N-H stretching of PU moved to lower wavenumbers. The red shift of the infrared bands of functional groups was attributed to the strengthened hydrogen bonding. The hydrogen bonding interactions between the stainless steel substrates and the polyurethane coating endowed the APS with excellent adhesive property and also promoted the evenly distribution of the photoluminescent particles in the polymer coating matrix.

This approach can be applicable in the fabrication of the photoluminescent materials. The APS can be used as signs and guiding post in remote areas without sufficient electricity supply and in the seas and rivers with complicated hydrological conditions.

This approach has provided a method to produce tough and durable luminescent signs for remote areas and dangerous seas and explained the functional mechanism of the combined application of metallic materials and non-metallic materials.

Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

As compared with homogeneous metals and alloys, cellular metals provide low density, high specific stiffness, high energy absorption and good damping, thus being interesting alternatives to employ as protection against shock and impact. Impact energy is dissipated through cell bending, buckling or fracture. The knowledge and computational modelling of the mechanical behaviour of metal foams structures is thus of great importance for real life applications. The purpose of this paper is to increase the knowledge of the differences in metallic hollow sphere structures' (MHSS) behaviour under dynamic loading, as compared with the corresponding behaviour under static loading and to determine the influence of inertia and loading rate.

Computational dynamical finite element analyses of representative volume elements (RVE) of MHSS have been performed considering varying loading rates. Partially bonded geometries are considered and the effect of the spheres' distribution is also taken into account.

The results of the numerical examples presented show that inertia plays an important role in the dynamic behaviour of this kind of energy‐absorbing structure. When compared with the corresponding values in the quasi‐static case, the effect of inertia makes the peak load higher. If the deformation rate is higher (greater than 1.39 m/s in the studied cases), the characteristic plateau usually present in compressed metal foams can vanish. For the geometries analysed, damage has a small influence on load‐deformation relations.

This paper presents and discusses differences between static and dynamic behaviour of partially bonded MHSS. There are few references in the literature covering this issue by means of numerical analysis.

Additive manufacturing technologies such as, for example, selective laser melting (SLM) offer new design possibilities for a wide range of applications and industrial sectors. Whereas many results have been published regarding material options and their static mechanical properties, the knowledge about their dynamic mechanical behaviour is still low. The purpose of this paper is to deal with the measurement of the dynamic mechanical properties of two types of stainless steels.

Specimens for dynamic testing were produced in a vertical orientation using SLM. The specimens were turned to the required end geometry and some of them were polished in order to minimise surface effects. Additionally, some samples were produced in the end geometry (“near net shape”) to investigate the effect of the comparably rough surface quality on the lifetime. The samples were tension‐tested and the results were compared to similar conventional materials.

The SLM‐fabricated stainless steels show tensile and fatigue behaviour comparable to conventionally processed materials. For SS316L the fatigue life is 25 per cent lower than conventional material, but lifetimes at higher stress amplitudes are similar. For 15‐5PH the endurance limit is 20 per cent lower than conventional material. Lifetimes at higher stress also are significantly lower for this material although the surface conditions were different for the two tests. The influence of surface quality was investigated for 316L. Polishing produced an improvement in fatigue life but lifetime behaviour at higher stress amplitudes was not significantly different compared to the behaviour of the as‐fabricated material.

In order to widen the field of applications for additive manufacturing technologies, the knowledge about the materials properties is essential, especially about the dynamic mechanical behaviour. The current study is the only published report of fatigue properties of SLM‐fabricated stainless steels.

The purpose of this paper is to present a dual-mode proximity sensor composed of inductive and capacitive sensing modes, which can help the robot distinguish different objects and obtain distance information at the same time. A systematic study of sensor response to various objects and the function of cooperation sensing is needed. Furthermore, the application in the field of robotic area needs to be discussed.

Numerical modeling of each sensing modes and simulations based on finite element analysis method has been carried out to verify the designed dual-mode sensor. A number of objects composed of different materials are used to research the cooperation perception and proximity sensing functions. In addition, the proposed sensor is used on the palm of a mechanical hand as application experiment.

The characteristics of the sensor are summarized as follows: the sensing range of inductive mode is 0-5.6 mm for detecting a copper block and the perceive range of capacitive mode is 0-5.1 mm for detecting a plastic block. The collaborative perceive tests validated that the non-ferromagnetism metals can be distinguished by inductive mode. Correspondingly, ferromagnetism metals and dielectric objects are differentiated by capacitive mode. Application experiments results reveal that both plastic bottle and steel bottle could be detected and differentiated. The experimental results are in agreement with those of simulations.

This paper provides a study of dual-mode proximity sensor in terms of design, experiments and application.