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This paper aims to introduce a high-temperature grease design method assisted by back propagation neural network (BPNN) and verify its application value.

First, the grease data sets were built by sorting out the base data of greases in a large number of literatures and textbooks. Second, the BPNN model was built, trained and tested. Then, the optimized BPNN model was used to search the unknown data space and find the composition of greases with excellent high-temperature performance. Finally, a grease was prepared according to the selected composition predicted by the model and the high-temperature physicochemical performance, high-temperature stability and tribological properties under different friction conditions were investigated.

Through high temperature tribology experiments, thermal gravimetric analysis and differential scanning calorimetry experiments, it is proved that the high temperature grease prepared based on BPNN has good high-temperature performance.

To the best of the authors’ knowledge, a new method of designing and exploring high-temperature greases is successfully proposed, which is useful and important for the industrial applications.

In high-temperature regions (tropical regions) temperatures rises in summer, which affects the performance of asphalt pavement. Therefore, we must consider the conditions of asphalt pavement, especially in these regions. This study aims to investigate the influence of high temperature on the stability performance of high-density polyethylene (HDPE) and crumb rubber powder (CRP) modified hot mix asphalt (HMA) using Marshall design parameters and rutting test.

In this study, three HMA mixtures with 4 per cent HDPE and 15 per cent CRP, 5 per cent HDPE and 10 per cent CRP, and 6 per cent HDPE and 5 per cent CRP concentrations were used for the Marshall stability test and dynamic stability (rutting test) at 60-75°C, and water stability test at 60°C.

The results showed that when test temperature was increased from 60°C to 75°C, the Marshall stability and dynamic stability of three HDPE- and CRP-modified HMA mixtures decreased, and these three HDPE- and CRP-modified HMA mixtures have a good moisture damage resistance. Of the three HMA mixtures with different HDPE and CRP concentrations, HMA mixtures with 5 per cent HDPE and 10 per cent CRP concentration exhibit optimal Marshall stability, dynamic stability and water stability.

This study showed the effects of high-temperatures changes on the stability performance of HDPE- and CRP-modified HMA mixtures.

The spectrally selective solar absorption paint is prepared from spinel-based mixed metal oxides with inorganic binder as a key component. Inorganic binder (furnace cement) is blended with mixed metal oxide pigment during synthesis. High temperature stability upto 1,100ºC is achieved by the use of this modified coating system. The purpose of this paper is to work on solar selective coating synthesis, and application of a coating as a water-borne paint is the additive key feature that helps in reduction of solvent use.

The paint was formulated using water-based system, and the main component of colorant was made by mixed metal oxide–based spinel pigment and highly temperature stable inorganic binder.

The paint formed shows excellent absorptive power with low emittance even at high temperature. Optical and thermal properties were determined along with adhesion, abrasion and other properties. The solar absorptance for these samples were as = 0.93–0.95 with corresponding thermal emittance of eT = 0.096 (at room temperature) and 0.2–0.22 (at elevated temperature 100°C).

The paint formed shows excellent absorptive power with low emittance even at high temperature. The paint can be applied in solar absorptive tower system. The obtained results indicated excellent thermal stability of prepared paint coatings. As inorganic binder was used, the paint has reduction in solvent use, and being water as a base, it is environment friendly, easy to apply and durable at high temperatures, as the binder itself is stable up to 1,500ºC.

A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by step synthesis was done for the spinel and cement mix formulations.

The pigment mix was synthesized by a solid-solid method where the inorganic binder was incorporated in the mix. The results suggested that CoCuMn-based spinel ceramic pigment with cement mix could be obtained at an annealing temperature of 1,100ºC for 1 h and the size, morphology and crystallinity of spinel mix were greatly influenced by the calcination temperature.

The pigment mix synthesized was applied as a coating to different substrates such as aluminum, glass and Mild steel. The results revealed that spectral selectivity of TSSS paint coatings based on the CoMnCu spinel ceramic mix was much better than that of solvent-based coatings for high-temperature applications. The presence of cement as an inorganic binder makes the functioning and application of paint easy as it becomes that of a waterborne type.

Ease of application, stability at high temperatures, best absorptivity at the solar selective spectrum and excellent adhesion properties for the selected surface are the key features of the designed pigment system. The applied pigment mix was studied as a coating to get the results for solar selective system.

This paper aims to discuss that a WC/Co-Cr alloy coating was applied to the surface of H13 steel by laser cladding.

The oxidation behavior of the WC/Co-Cr alloy coating at 600°C was investigated by comparing it with the performance of the steel substrate to better understand the thermal stability of H13 steel.

The results showed that the WC/Co-Cr alloy coating exhibited better high-temperature oxidation resistance and thermal stability than did uncoated H13 steel. The coated H13 steel had a lower mass gain rate and higher microhardness than did the substrate after different oxidation times.

The WC/Co-Cr alloy coating was composed of e-Co, CW3, Co6W6C, Cr23C6 and Cr7C3; this mixture offered good thermal stability and better high-temperature oxidation resistance.

This study aims to develop a bimodal nano-silver paste with improved mechanical property and reliability. Silicon carbide (SiC) particles coated with Ag were introduced in nano-silver paste to improve bonding strength between SiC and Ag particles and enhance high-temperature stability of bimodal nano-silver paste. The effect of sintering parameters such as sintering temperature, sintering time and the proportion of SiC particles on mechanical property and reliability of sintered bimodal nano-silver structure were investigated.

Sandwich structures consist of dummy chips and copper substrates with nickel and silver coating bonded by nano-silver paste were designed for shear testing. Shear strength testing was conducted to study the influence of SiC particles proportions on the mechanical property of sintered nano-silver joints. The reliability of the bimodal nano-silver paste was evaluated experimentally by means of shear test for samples subjected to thermal aging test at 150°C and humidity and temperature testing at 85°C and 85 per cent RH, respectively.

Shear strength was enhanced obviously with the increase of sintering temperature and sintering time. The maximum shear strength was achieved for nano-silver paste sintered at 260°C for 10 min. There was a negative correlation between the proportion of SiC particles and shear strength. After thermal aging testing and humidity and temperature testing for 240 h, the shear strength decreased a little. High-temperature stability and high-hydrothermal stability were improved by the addition of SiC particles.

Submicron-scale SiC particles coated with Ag were used as alternative materials to replace part of nano-silver particles to prepare bimodal nano-silver paste due to its high thermal conductivity and excellent mechanical property.

Modern technology is giving some new requirements for the lubricating grease, and there are also some weaknesses for the existing diurea grease, especially its lower anti‐shear stability. This paper aims to address this issue. In this work, in order to meet the new industrial requirements and improve the weaknesses of diurea grease, the tetraurea grease has been synthesized.

Tetraurea grease was synthesized by multi‐steps, characterized by FT‐IR, NMR, ESI‐MS. The properties were evaluated by the ASTM method, such as dropping point, penetration, oil separation and shear stability, as well as four‐ball machine experiment.

The result shows that tetraurea grease is indeed synthesized successfully and it has a better performance than the existing diurea grease, the main properties of it have been increased, such as high‐temperature performance, structural stability, anti‐shear stability and extreme pressure performance.

This enriches the kinds of polyurea grease. Enhanced lubricating grease performance would have better industrial prospects, and a larger application field than existing diurea grease.

This paper aims to provide a fabrication and measurement of a highly stretchable pressure sensor with a “V-type” array microelectrode on a grating PDMS substrate.

First, the “V-type” array structure on the silicon wafer was fabricated by the MEMS technology, and the fabrication process included ultra-violet lithography and silicon etching. The “V-type” array structure on the master mold was then replicated into polycarbonate, which served as an intermediate, negative mold, using a conventional nanoimprint lithography technique. The negative mold was subsequently used in the PDMS molding process to produce PDMS “V-type” array structures with the same structures as the master mold. An Ag film was coated on the PDMS “V-type” array structure surface by the magnetron sputtering process to obtain PDMS “V-type” array microelectrodes. Finally, a PDMS prepolymer was prepared using a Sylgard184 curing agent with a weight ratio of a 20:1 and applied to the cavity at the middle of the two-layer PDMS “V-type” array microelectrode template to complete hot-press bonding, and a pressure sensor was realized.

The experimental results showed that the PDMS “V-type” array microelectrode has high stretchability of 65 per cent, temperature stability of 0.0248, humidity stability of 0.000204, bending stability and cycle stability. Capacitive pressure sensors with a “V-type” array microelectrode exhibit ideal initial capacitance (111.45 pF), good pressure sensitivity of 0.1143 MPa-1 (0-0.35 Mpa), fast response and relaxation times (<200 ms), high bending stability, high temperature/humidity stability and high cycle stability.

The PDMS “V-type” array structure microelectrode can be used to fabricate pressure sensors and is highly flexible, crack-free and durable.

MOST of the aircraft engines of the 1900 era were little more than adaptations of the existing reciprocating internal combustion engines used in motor cars, but progressive design improvements eventually led to the very efficient power plants of high horsepower which had by the 1940's enabled piston‐engined bomber aircraft to reach cruising speeds of 300 m.p.h. and piston‐engined fighter aircraft to attain level‐flight speeds in excess of 400 m.p.h. At this stage, piston engines had almost reached their peak performance and aircraft speeds could be significantly increased only by the adoption of some radically different type of engine. The development of the gas turbine resulted in this new power plant and aero gas turbines are now in the final stages of replacing piston engines as propulsive units for medium and large aircraft.

The review glances upon the colorants used for printing on ceramic substrates by ink jet technology and techniques, chemistry involved during the selection of the colorants.

The ink jet technology is an easy and a convenient technique, specially designed colorants are used for such applications with tailor made properties and features.

New developments in technology and chemistry of colorants to achieve successes in application studies of ceramic substrates.

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This review glances upon the history, development and practical approach of the current techniques with available dyes and pigments and the techniques involved during the synthesis and application.

The review paper provides information about the development of the inkjet technique on ceramics and available colorants with methods.