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To understand the service performance of full ceramic ball bearings under extreme working conditions and improve their service life, dynamic characteristic tests of full ceramic ball bearings under ultra-low temperature conditions were carried out by a low-temperature bearing life testing machine, and temperature rise and friction were measured under extreme low-temperature environment.

The heat-flow coupling model of bearing was established by CFD software, and the test results were further analyzed.

The results show that the temperature rise of the bearing is not obvious in the liquid nitrogen environment. With the increase of the chamber temperature, the lubrication state of the bearing changes, resulting in the temperature rise of the outer ring of the bearing. As the temperature of the test chamber increases, the friction force on the bearing increases first and then decreases under the action of multifactor coupling.

The research results provide test data and theoretical basis for the application of all-ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

In order to evaluate the rheological properties of asphalt more comprehensively and effectively, and to explore and discuss the practicability of relevant models in the evaluation of the rheological properties of asphalt.

Based on the rheological and viscoelastic theories, temperature scanning, frequency scanning and multiple stress creep recovery (MSCR) tests of different modified asphalt were carried out by dynamic shear rheometer (DSR) to obtain relevant viscoelastic parameters and evaluate the high temperature properties of different modified asphalt. Based on the time-temperature equivalence principle, the main curve was constructed to study the viscoelastic properties of asphalt in a wider frequency domain. The main curve was fitted with the CAM model, and the rheological properties of different modified asphalt were evaluated through the analysis of model parameters. The creep stiffness and creep velocity of different modified asphalt were obtained through the rheological test of bending beam (BBR), and the low-temperature performance of different modified asphalt was analyzed by using Burgers model to fit the creep compliance.

The results show that the high temperature rheological properties of several modified asphalt studied in the test are ranked from best to worst as follows: PE modified asphalt > SBS modified asphalt > SBR modified asphalt. Short-term aging can improve the high temperature performance of asphalt, and different types of modifiers can promote or inhibit this improvement effect. Based on BBR test and Burgers model fitting analysis, SBR modified asphalt has the best low temperature performance, followed by SBS modified asphalt, while PE modified asphalt has poor low temperature performance, so it is not suitable to be used as road material in low temperature area.

Combined with effective evaluation methods, the rheological properties of asphalt at different temperatures and angles were systematically evaluated, and the evolution of rheological properties of asphalt characterized by model parameters was further analyzed by advanced model simulation.

Reports results from studies conducted on a polyfunctional amine adduct epoxy curing agent (EPI‐CURE DPC‐3293) as a means to design low temperature cure coatings. Through the judicious choice of epoxide resins and amine‐functional curing agents, relatively fast reaction rates and resistance to moisture and humidity are maintained under low‐temperature cure conditions, and that is evidenced by a good balance of performance properties of coating films. We have used differential scanning calorimetry (DSC) to study the extent of reaction as well as the glass transition temperatures (T_g). Electrochemical impedance spectroscopy (EIS) has been used to predict the barrier properties of coating films. These results are compared with epoxide resins cured with a phenalkamine curing agent to illustrate some of the unique advantages of using multifunctional amine adduct curing agents for the curing of epoxide resins under sub‐ambient cure conditions for a multitude of end‐use applications.

The purpose of this paper is to investigate the effects of liquid carbon dioxide (LCO₂) on grinding of stainless steel.

A factorial experimental approach was used to compare the LCO₂'s performance against grinding under dry air and emulsion coolants.

The experimental results have a great use to practitioners. It was found that under special conditions, LCO₂ proves to be an alternative coolant for grinding of temperature sensitive materials. Furthermore, grinding under LCO₂ conditions produced the lowest tangential force, while the normal forces were close to the values found under emulsion fluid environment. When compared to grinding under dry conditions, LCO₂ coolant was successful in reducing the work piece temperatures. LCO₂ and emulsion conditions inhibit work hardening by reducing material deformation at the grinding zone.

The paper shows that sub‐zero temperature coolants have the ability to bring about lower grinding temperatures than what is typically achieved under conventional fluids.

A new Protection of Consumers (Trade Descriptions) law to replace existing legislation was before the House of Lords—it had a second reading and passed to the Committee stage but has now lapsed because of the Election —as the outcome of the Molony Committee on Consumer Protection which made its final report about three years ago. Merchandise Marks law has proved extremely valuable protection for the consumer in a wide field of misdescription and in the narrower sphere of food control a useful measure for supplementing Sect. 6, Food and Drugs Act, 1955, especially where the latter seems less suitable in application. The broad purpose of the Merchandise Marks Acts is to deal with misdescription of goods—false trade description—and as far as food is concerned, this is not always a matter of quality. On rare occasions it has been seen to work in reverse. In the curious case of Essex County Council v. Tuckwell (Butchers) Ltd., 1964, where the defendant had inadvertently supplied English instead of the New Zealand lamb ordered, generally accepted as being meat of better quality, the L.C.J. held that there was no defence against the charge of having sold meat with a false trade description.

The performance of epoxy coating on metal substrate at low temperature and high humidity application has adverse effect on cure rate, film properties and adhesion. In recent years, several advanced amine cross-linking agents having superior curing ability at low temperature application environment have been introduced. The aim of this paper is to study the properties of epoxy-based coating cured with different cross-linking agents designed for low temperature application at different environmental conditions.

Series of cross linking agents such as modified cycloaliphatic amine (H1), polyamine adduct (H2), modified aliphatic ketamine (H3), phenalkamine (H4) and phenalkamide (H5) have been studied to evaluate their performance in epoxy compositions when cured at four environmental conditions, i.e. at ambient and sub-ambient temperatures with 60 and 90 per cent relative humidity, respectively. The effect of curing conditions was investigated by evaluating different physico-mechanical properties. Dynamic mechanical analyser technique was used to determine glass transition temperature (T_g) and cross-link density (ρ) of coatings. Anticorrosive properties of coatings also have been studied by electrochemical impedance spectroscopy.

The outcome of this study is expected to generate new insight into the curing behaviour of epoxy coating using different cross-linking agents which are recommended for low temperature application. Optimum physico-mechanical and corrosion resistance properties have been obtained by phenalkamine curing agent at low temperature and high humidity condition.

This study is an experimental approach to select the better cross-linking agent for low temperature application. Different test conditions were measured for understanding the performance of epoxy coating cured at different environmental condition.

The understanding reaction mechanism of the epoxy resin with cross-linking agent at different environmental condition is the great challenge and is hardly investigated in the literature. Therefore, in this research, the influence of climatic conditions and type of cross-linking agents on curing behaviour of epoxy-based coating was investigated.

The type 120 emergency valve is an essential braking component of railway freight trains, but corresponding diaphragms consisting of natural rubber (NR) and chloroprene rubber (CR) exhibit insufficient aging resistance and low-temperature resistance, respectively. In order to develop type 120 emergency valve rubber diaphragms with long-life and high-performance, low-temperatureresistant CR and NR were processed.

The physical properties of the low-temperature-resistant CR and NR were tested by low-temperature stretching, dynamic mechanical analysis, differential scanning calorimetry and thermogravimetric analysis. Single-valve and single-vehicle tests of type 120 emergency valves were carried out for emergency diaphragms consisting of NR and CR.

The low-temperature-resistant CR and NR exhibited excellent physical properties. The elasticity and low-temperature resistance of NR were superior to those of CR, whereas the mechanical properties of the two rubbers were similar in the temperature range of 0 °C–150 °C. The NR and CR emergency diaphragms met the requirements of the single-valve test. In the low-temperature single-vehicle test, only the low-temperature sensitivity test of the NR emergency diaphragm met the requirements.

The innovation of this study is that it provides valuable data and experience for future development of type 120 valve rubber diaphragms.

This study aims to investigate the basic mechanical properties of inflatable antenna reflector material under high-low temperatures.

Uniaxial tensile tests of Kapton (polyimide) foils were conducted in this paper. Kapton foils with a thickness of 25 µm were used and the strip specimens were manufactured according to the machine direction and the transverse direction of the foils.

The stress–strain curves of the foils were obtained under ten temperature conditions (−70°C, −40°C, −10°C, 0°C, 20°C, 50°C, 80°C, 110°C, 140°C, 170°C) after uniaxial tensile tests. Generally speaking, such stress–strain curves are highly nonlinear, and Kapton can be classified into some kind of ductile material without obvious yielding point.

The tests results provide a basis for partial coefficients of Kapton foils strength design value, and meanwhile provide basic material data for the extreme temperature field test in orbit for the inflatable antenna structure in the future.

Based on the curve itself and strain energy theory, for the first time the equivalent yielding point was determined and the mechanism of constitutive curve changing with temperature was explained. Based on curves above, tensile strength, elongation at break, equivalent yielding stress, yielding strain and elastic modulus were analyzed and calculated. By analyzing the mechanical parameters above, the fitting formulas with temperature as the variable were given.

The paper aims to present the influence of the co-firing process conditions of low temperature co-fired ceramics (LTCC) on the deformation of thin LTCC membranes.

The statistical design of the experiment methodology was used in the frame of these investigations to reduce the time and costs of the experiments and to ensure easier interpretation of the obtained results. Moreover, this conception permits the rough estimation of the membrane deflection fired at optimal process conditions.

The applied design of the experiment methodology allowed the researchers to find the optimal co-firing process conditions and to estimate the membrane deflection at the optimal process conditions. The estimation fits well with the results of real measurement that was conducted to confirm the estimation precision.

The experiment was conducted for only one type of LTCC, DP951. The precision of the design of the experiment optimization and estimation of the response at optimal conditions depend on the described object. Therefore, the findings of this paper do not have to be generally true for other LTCC tapes, and if other LTCC tapes deformation should be investigated, then similar analysis shall be conducted for them.

The deformation of LTCC membranes affects the sensitivity and repeatability of LTCC acceleration and pressure sensors. Hence, the decrease of membrane deflection increases the usability of LTCC in such applications.

This paper presents simple optimization of co-firing process conditions of LTCC devices using statistical design of the experiment.