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This paper presents a modified relaxation model of plasticity (MRP model) that captures the non-monotonic stress–strain relation, especially the yield point phenomenon (YPP), observed in some metallic materials subjected to relatively low loading rates. The YPP refers to a distinct stress decrease during the initial plastic deformation stage. The relaxation model of plasticity (RP model) was developed from the incubation time approach, which takes into account the time sensitivity of materials to describe various stress–strain relationships. Based on experimental facts for copper whiskers, silver whiskers, and magnesium alloys Mg–0.3Ca (wt%) and Mg–1.0Al–1.0Ca–0.4Mn (wt%) with different grain sizes, the descriptive abilities of the MRP model are compared with the original RP model. Thus, the temporal nature of the stress drop effect that reveals itself even for low strain rate conditions is established. Additionally, the impact of grain size on the incubation time is examined, which indicates a noticeable trend of increasing incubation time as grain size decreases.

The paper describes methods for preparing natural fabrics for direct printing. The influence of preliminary plasma treatment of natural fabrics on color fastness to washing has been studied. Cotton fabrics and Tencel fabric made from eucalyptus fibers have been examined. Plasma treatment was used to modify the fabrics. The plasma type was nonequilibrium, low-temperature; capacitively coupled radiofrequency discharge plasma in air. It has been established that the plasma treatment of the fabrics in air at a power of 2000 W helps to increase color fastness to washing by up to 82%.

The paper presents the results of experimental studies of the effect of capacitive discharge of low-temperature plasma on the main characteristics of medical nonwovens based on polypropylene. The modes of plasma modification of nonwoven materials are established, at which an increase in absorbency of fabrics by 20.1–106.9% is achieved.

The article describes methods for modifying glass and basalt fibers and threads, and composite materials from them. Special attention is paid to plasma methods. Twisted glass thread and basalt twisted thread are investigated in the work. Plasma treatment was used to modify the threads. The type of plasma is nonequilibrium, low-temperature; the type of discharge is high-frequency capacitive. The results of research of thread properties, such as morphological changes and breaking load of threads. The plasma-treated and non-treated samples of threads were compared. The modes of plasma modification of threads in which the increase of breaking load strength of glass threads up to 23 % and of basalt threads up to 10 % is achieved have been established.

The article considers changes in the properties of Rusar-S brand aramid fiber due to the treatment of low-pressure plasma of radiofrequency capacitive discharge. After modification, there was recorded the growth of hydrophilicity in the environment of inert and oxidizing gases. The paper discusses the results of IR spectroscopy of Rusar-S aramid fiber before and after plasma modification. An obtained data of research can explain the influencing mechanisms of RFC discharge plasma of a low-pressure on the properties of aramid fiber.

The article describes the methods of modification of glass fibers, threads and composite materials made of glass fibers. In the work, the twisted glass thread and electrically insulating glass tape were investigated. Plasma treatment was used to modify the threads. Plasma type is nonequilibrium, low temperature; type of discharge—radio-frequency capacitive. The aim of the work is to study the strength properties of yarns and tapes, before and after treatment in low-temperature plasma.The plasma modification of the threads in the argon/propane-butane and propane-butane gases medium at 4 kV has been found to increase the breaking load strength of glass threads up to 23%.The subsequent treatment of the tapes in the propane butane medium increases the strength to 5%.

The paper compares two methods of the carbon fiber surface cleaning for their following modification and more complete realization of its physical and mechanical properties. The aim of the work is to identify the optimal method of pre-modification of carbon fiber, which in the future will be used as a filler of polymer binder in the composite. The results demonstrate successful surface cleaning, preservation of the level of physical and mechanical properties of fibers, increase of capillarity index.

The article studies the effect of plasma modification on the flame retardant properties of blended fabrics. The regime of plasma treatment is revealed at which effective and uniform solution absorption of the flame retardant composition of textile materials is achieved. It was found that the most effective fixing of the flame retardant is carried out on samples that underwent double plasma treatment before and after impregnation with the flame retardant.

The article deals with the method of the modification of polyester fabrics used to create a coating that protects against electromagnetic radiation. As a method of modifying the technical properties of the polyester material, treatment in a magnetron spraying unit is proposed. Aluminum and titanium are used as sprayed materials. The use of the studied samples of metallized tissue leads to the significant decrease in the levels of electromagnetic fields.

The article considers issues related to the effect of plasma treatment on the properties of jute fabrics and their component fibers. The modes of plasma treatment of jute fabrics were selected. The surface changes of jute fibers were studied by using scanning electron atomic force microscopy. According to the results of the experiments, an increase in the strength characteristics of jute fabrics treated with radio-frequency capacitive discharge was revealed, and the roughness of the surface of jute fibers was estimated.