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The purpose of this paper is to provide a new entry board for drilling holes on the PCBs, superior in heat removal effect, lubricating effect and hole locating effect in forming holes, resulting in an excellent process of forming holes with a high quality.

With the mixture of PEG, PEO and adhesive used as endothermic and lubricant resins and aluminium foils used as baseplates, a series of coated and aluminous entry boards (CABs) for PCB drilling were successfully prepared. Scanning electron microscopy (SEM) was employed to observe the surface appearance of the entry boards. The endothermic and lubricant effect of the resin applied on the CABs was characterized by differential scanning calorimetry (DSC) and polarizing microscope (POM). Moreover, the CABs' good drilling properties were tested when they were used for PCB drilling.

From the result of SEM analysis, it was found that compared to the common aluminium foil, the surfaces of the CABs were smoother and flatter, which could improve the hole location accuracy and reduce the drill breakage. By means of the DSC and POM, the endothermic and lubricant effect of the CABs was proved. The crystalline substances (PEG and PEO) in coated resin could absorb the heat of the drill bit from heat generation and lubricate it through the phase transition of they own when a hole was being made, which could give high‐quality holes with good production efficiency. The drilling tests showed that due to the endothermic and lubricant resins, the CABs were superior to the common aluminium foil, not only in hole location accuracy, but also in hole wall quality and protection of a drill bit.

This paper has a remarkably high industrial practicality in the PCB manufacture process.

This paper aims to provide a new drilling entry board for printed circuit board (PCB) process, superior in heat dissipation, lubrication, water solubility and hole location accuracy, achieving an excellent drilling process.

Using a mixture of polyethylene glycol (PEG) and water-soluble adhesives as hydrosoluble, endothermic and lubricant resins and aluminum foils as baseplates, a series of coated and aluminous entry boards (CABs) for PCB drilling was successfully prepared. The surface appearance of the entry boards was observed clearly by scanning electron microscopy (SEM). The endothermic and lubricant effects of the resins applied on the CABs was characterized by differential scanning calorimetry (DSC) and their water solubility was tested in the normal-temperature water (25°C). Moreover, the CABs’ good drilling properties were tested when they were used for PCB drilling.

The SEM analysis showed that the surfaces of the resin layers coated on the CABs whose coating thicknesses were less than 80 μm were smoother and flatter, which could improve hole location accuracy and reduce drill breakage ratio. By virtue of DSC, the endothermic and lubricant effects of the CABs were proven. The fusion of PEG in the resin layers could absorb the heat produced by drilling, restrain the temperature of the drill bit and hole rising and lubricate the drill bit efficiently when a hole was being drilled, which could achieve high-quality holes with good production efficiency. The water-soluble test showed that the prepared CABs had excellent water solubility at normal temperature, enabling the resin left on the hole walls and in the flute of the drill bit to be washed away easily and thereby improving the drilling efficiency and quality. The drilling tests showed that the increase in the thickness of the CABs’ coating could improve the hole location accuracy and alleviate the bit wear. In addition, the suitable coating thickness could ensure the firm adhering of the resin coating the aluminum foil, effectively avoid drill intertwist and prevent the resin debris from blocking the drilled holes on the surface of the entry board, which could hinder chip removal, resulting in poor hole wall quality and drill breakage.

This paper has a remarkably high industrial practicality in the PCB manufacture process.

Water-based graphite lubricants have good lubricity in the process of metal forming, especially for hot-rolling seamless pipe. Although the use of water as a working fluid system instead of conventional mineral oil has many advantages for the fuel consumption, post cleaning and a new type of lubricant, the graphite contaminated the machine and workers for its physical properties. From the global environmental protection viewpoint, it is urgent to develop a kind of benign material.

Magnesium hydroxide which has the average particle size of 10 μm was chosen as a base material without further modification and pretreatments. On the HT-1000 high-temperature tribometer, the influence of temperature and lubricant materials on the friction coefficient was studied. The tribological performance at 900^°C provided evidence under high temperature for exploring a new lubricant material.

Tap water-based brucite lubricant will open a new chapter in the industrial lubrication, effectively avoiding many unfavorable factors caused by graphite lubrication, such as conductivity, pollution and energy loss. Meanwhile, it expanded the application of brucite as flame-retardant agent, catalyst, water treatment agent and so on.

It is a new and environmental lubricant to tap water-based brucite lubricant. And specially, the preparation process of lubricant is simple and economical.

The tribological properties of muscovite and its thermal-treated products as lubricant additives in lithium grease were investigated. The effect of thermal temperature on the crystal structure and tribological properties of muscovite was studied. This study aims to explore the tribological mechanism of muscovite and optimize a proper thermal activation temperature, thus further improving the tribological properties.

The crystal structure of muscovite samples was characterized by SEM, TG-DSC, XRD and FTIR. The tribological properties of grease samples were investigated using a four-ball tribotester and the worn surface was analyzed by SEM and EDS.

The excellent tribological properties of muscovite can be ascribed to the layer structure and lubricant film formed on the worn surface. Thermal temperature at 500-600°C increases the surface activity and oxygen releasing capability, and thus favors the formation of lubricant film and accordingly further improves the tribological properties. However, the layer structure is destroyed and hard phases such as alumina and amorphous appear after thermal temperature activated beyond 1000°C, as it results in the aggravation of friction and wear.

To the authors’ knowledge, it is the first to study the effect of thermal temperature on the crystal structure and tribological properties of muscovite. The tribological mechanism of muscovite particle and its thermal-treated products was disclosed.

The purpose of this paper is to review the new trends in plastic additives, with special focus on developments in food packaging materials.

Phenomenological research has brought awareness and increased insight into the role of various plastic additives on the packaging of foods. The approach is based on the current trends and the industrial protocols for the additives used in plastic polymer processing for the development of food packaging materials.

Packaging of foodstuffs is a dynamic process which continually responds to the changes in supply and demand which are the result of adaptations to the varying demands of the consumer, changes in retail practices, technological innovations, new materials and developments in legislation, especially, with respect to environmental concerns. A wide range of additives is available for enhancing the performance and appearance of food packaging, as well as improving the processing of the compound. Polymer additives are important areas of innovation for packaging materials.

The paper reviews and summarizes the recent developments in the functionality of different additives, along with their advantages and disadvantages, currently being used to enhance the properties of food packaging materials that can positively influence the environment within the packaging for the increased demand for raw or processed foods.

This study aims to systematically investigate the tribological behaviors of metal and polyethylene using lubricants composed of four synovial fluid (SF) components. In addition, the changes in protein conformation during wear were analyzed to establish the correlation between protein conformation and tribological properties.

A pin-on-disk tester with multidirectional sliding motion was used for tribological properties observation between metal and polyethylene pairs. Simulated SFs with four main constituents were used as the testing lubricants. Differential scanning calorimetry and Raman were used to characterize the changes in protein conformation during wear.

The coupling of lipids and hyaluronic acid further suppressed protein denaturation. The protein structures of the adsorption film and the ensnared protein chains in the friction zone were maintained to a certain extent, thus improving the friction and wear of polyethylene.

These findings established the correlation between protein conformation and friction and wear, promoting the understanding of the lubrication mechanism of artificial joints.

Serpentine is usually added into the lubricant oil to form a self-repairing protective layer on worn ferrous surface. But few works have paid close attention to the preparation of composites with the addition of serpentine. In this work, serpentine reinforced Al matrix composites were successfully prepared to be industrial lubrication components. And its fabricating parameters, compressive strength and tribological properties were analyzed.

An MM-W1 three-pin-on-disk apparatus was used to investigate the tribological properties. The worn surface, microstructure and cross-sectional morphologies were characterized by scanning electron microscopy equipped with energy dispersive spectroscopy. The compression test was carried out on a universal testing machine. An X-ray diffractometer was used to investigate the phase constitutions. The decomposition temperature of serpentine powders was investigated by a thermal analyzer, which allows simultaneous differential scanning calorimetry and thermogravimetry. With the help of finite element method model, a diagrammatic model of the self-repairing surface layer was developed to analyze the anti-friction mechanism.

Through evaluating density and Brinell hardness, sintering at 560°C for 3 h are the appropriate parameters for fabricating the composites. Compressive strength was increased by the addition of serpentine. A self-repairing surface layer was formed, reducing the friction coefficient. And a diagrammatic model of the self-repairing surface layer was developed to analyze the anti-friction mechanism.

Serpentine was added in fabricating the Al matrix composites for the first time. Sintering parameters were optimized to make better Al/Si/serpentine composites. Compressive strength was increased by the addition of serpentine. A self-repairing surface layer was formed, reducing the friction coefficient under the dry sliding condition. And a diagrammatic model of the self-repairing surface layer was developed to analyze the anti-friction mechanism. It is hoped to be helpful in further confirming the factors for the formation of the self-repairing surface layer, and in designing a new industrial anti-friction composite used for dry sliding conditions.

The aim of this work is to synthesize neopentyl glycol oligoesters based on adipic acid and rapeseed oil (NOAR) which may be used as the renewable and environmentally acceptable base fluids to replace mineral oils in the future.

Oligomeric intermediates were synthesized in the first esterification of neopentyl glycol with adipic acid and characterized by Gas Chromatography-Mass Spectrometer (GC-MS) to calculate the average oligomerisation degree. NOAR were synthesized in the second esterification of oligomeric intermediates with rapeseed oil fatty acid. The effects of average oligomerisation degree on the viscosity, viscosity index, pour point, oxidative stability and biodegradability of NOAR were investigated; the tribological properties and thermal stability of NOAR were evaluated by four-ball tribometer and TGA, respectively.

Results show that with the increase of average oligomerisation degree from 2.10 to 4.34, the viscosity of NOAR increased from 101.1 to 182.0 (mm2/s) at 40°C and 18.3 to 30.1 (mm2/s) at 100°, respectively, and their oxidation stability can be improved as well. The yields of NOAR were 83.3-89.4 per cent, and the evaluated properties were as follows: viscosity index of over 200, pour point of below −43°C, biodegradation rate of more than 96 per cent, maximum non-seizure load (PB value) of 784 N, wear scar diameters of 0.40 mm and thermal decomposition temperature of higher than 300°C.

This work provides a method to synthesize rapeseed oil-based oligoesters which can serve as the renewable and environmentally acceptable base fluids with tunable viscosity by controlling the oligomerisation degree of esterification.

In introducing the subject some of the advantages of pneumatics for high speed aircraft are pointed out. Owing to its suitability for airborne conditioning systems, it is pointed out that it is logical to combine this characteristic in producing a combined air turbine and electric generator without the need of a separate cooling system. This was the thought behind the design of the Turbonator AC generating machine It includes a turbine wheel integral with the generator which is arranged to allow the turbine exhaust gas to pass over the generator for cooling purposes. The generator rotor windings are supported solidly by titanium retainers. Rotor bearings may either be of the sealed oil type or air bearings. Both have been tested, but, while the former is the simplest and suitable for present‐day standards, the air bearing has distinct possibilities for future uses. Thrust loads are taken up by an air bearing using the turbine wheel face as the bearing journal. No liquid is therefore used as a lubricant, thereby eliminating this high temperature problem. Materials for the generator are considered, one of which is ceramic insulation. Consideration was given to the inductor generator, but although this type of machine may be more suitable for high speeds, the rotating winding generator displays more advantages. A test rotor of the latter type has withstood speeds of 62,000 r.p.m. which is 25 per cent above normal speeds. The recent availability of a 24,000 r.p.m. generator makes it possible to eliminate a reduction gear.

Silicone softeners are widely used in the textile industry to improve the performance of textile products. The thermal characteristics and flammability of polyester fabrics can be influenced by these compounds, which need to be considered, as important issues of human safety. The purpose of this paper is to investigate the changes induced on the polyester fibre by silicone softener treatment using a pad/dry/cure method.

The fibres were first treated with nano‐ and microemulsion silicone softeners. The influence of the silicone emulsion type on thermal properties and flammability of the resultant samples were investigated by various analytical techniques, namely, the differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamical mechanical thermal analysis (DMTA) and horizontal flammability test (HFT).

Results showed that the silicone softeners increase the thermal degradation and flammability of the polyethylene terephthalate (PET) substrate.

The paper's study of thermal and flammability of the silicone‐treated sample is novel and can be used to optimize the properties of silicone polymers during production and consumption.