Metal-polymer Material Research Articles

Characterization of friction between metal-polymer material pairs with different speeds and surface pressures

Abstract Engineering design requires accurate knowledge of the friction conditions of material pairs. The friction coefficient (static or dynamic) depends on many parameters in addition to the pairs of materials used (e.g. surface roughness, temperature, humidity, surface pressure, etc.). In this study, based on our own measurements, we present the friction conditions of an aluminum (Al 6082-T6) – polypropylene homopolymer surface pair under different surface loads (5-15 MPa) and different relative speed differences (4-8–48-96 mm/min). The results of the experiments show that the static and dynamic friction coefficients decrease with the increase of surface load. As relative speed increases, the dynamic coefficient of friction increases, while the static coefficient of friction can be considered constant.

INVESTIGATION OF THE INFLUENCE OF SUPERPOSITION OF HIGH-FREQUENCY VIBRATIONS DURING THE CURING OF A METAL POLYMER ON ITS STRUCTURE

The article provides a description and results of an experimental study on the compaction of a metal-polymer material under the action of ultrasound, which is supposed to be used as a reinforcing component of various composite engineering systems. The scheme of the experiment and the used equipment and materials, measuring equipment are given. A brief mathematical analysis of the dynamics of a viscous fluid flow and the laws describing these processes is presented. A hypothesis has been formulated about an increase in the density of the metal polymer under the action of ultrasound, due to the introduction of additional vibration energy and its dissipation in the metal polymer, which should lead to a decrease in viscosity. The obtained metal-polymer samples were examined visually and using a durometer, the results are presented as images of samples sections and tabular data. Based on the data obtained, a histogram of the dependence of hardness and the number of gas pores on the time of ultrasonic exposure was constructed. In conclusion, an analysis of the obtained data is given, and conclusions are drawn about the effect of using ultrasound during pouring and curing of a viscous metal polymer. New directions for studying the effect of low-frequency vibrations on the viscosity of the metal-polymer composition are proposed in order to create technological equipment for the implementation of the technology for creating composite machine-building systems based on metal-polymer.

Methodological Foundations Protective Structures Development for Shielding Electromagnetic and Acoustic Fields

In many cases the simultaneous protection against electromagnetic and acoustic fields of wide frequency ranges is required. The complexity of such a task lies in the impossibility of significantly reducing low-frequency sound levels with traditional sound-absorbing materials, as well as the different requirements for materials that shield low-frequency and high-frequency electromagnetic fields. It is proposed to solve this problem by creating a two-layer structure, the front surface of which is solid, and the inner surface is perforated. The front panel can be made of non-conductive material. It is a variant of the Bekeshi panel and is mainly intended to reduce the level of low-frequency sound of a certain frequency with high amplitude. The perforation of the internal (metal) panel is chosen based on the need to provide shielding of electromagnetic and acoustic fields of certain frequencies or frequency bands. A calculator is provided for calculating the required panel parameters (linear dimensions, thickness, hole diameters, their number per unit of surface area). It is advisable to fill the space between the panels with a sound-absorbing material, for example, granulated polystyrene. It provides sound absorption of medium and high frequencies and makes the design broadband. The use of ferromagnetic material of the inner panel provides protection against the magnetic component of the ultra-low frequency electromagnetic field (mainly industrial). The perforation of the panel is calculated based on the waveguide theory of high-frequency electromagnetic waves. The results of tests of the effectiveness of facing metal-polymer material in the form of tiles are presented. The performance of the material is satisfactory for most industrial and domestic conditions. Determination of the mechanical properties of the material (Young's modulus, shear modulus and Poisson's ratio) showed that it is not inferior to known materials even with a large content of shielding substance. In order to rationalize the design of the structure, a priority factor and frequency (frequency band) is selected on the basis of live measurements of the electromagnetic and acoustic spectra. It is shown that the calculations have large volumes, and the solution of two-factor optimization problems is not always possible. Appropriate creation of application software to simplify the process of designing protective structures and rationalizing panel parameters based on the principles of reasonable sufficiency.

Computer modeling and verification of mechanical properties of metal-polymer composite materials used in the technological process of layer-by-layer growing of parts used in the technological process of layer-by-layer growing

The article presents the results of computer modeling of the microstructure of a composite material consisting of a polyamide matrix and metal inclusions. The researched composition is one of the advanced trends in the production of materials for advanced MIM technologies. This paper describes the design of a new pressing device to produce composite rods. Computer modeling of mechanical properties of composite metal-polymer material was performed in the high-level CAD system DIGIMAT module MF. Micro-level modeling of the composite made it possible to establish the relationship between the percentage of inclusions and the upper yield strength of the material and the influence of the shape of the inclusions on the tensile strength of the designed material. The computational experiment results were verified with the results of the field experiment for the samples produced by the injection molding technology and the 3D printing technology.

Гибридный металлополимер на основе полиметилметакрилата с внедренными металлическими наночастицами как активная среда оптоакустического генератора ультразвука

A study was made of a hybrid metal-polymer material consisting of polymethyl methacrylate (PMMA) and nanoparticles distributed throughout its volume, silver, gold, copper or aluminum. The effective permittivity and absorption cross section are calculated, and the processes of temperature relaxation are modeled. It has been shown that mixtures of PMMA with silver, copper, aluminum, or gold nanoparticles can be used as an active medium in optoacoustic ultrasound generators.

A hybrid metal polymer based on polymethyl methacrylate with embedded metal nanoparticles

A study was made of a hybrid metal-polymer material consisting of polymethyl methacrylate (PMMA) and nanoparticles distributed throughout its volume, silver, gold, copper or aluminum. The effective permittivity and absorption cross section are calculated, and the processes of temperature relaxation are modeled. It has been shown that mixtures of PMMA with silver, copper, aluminum, or gold nanoparticles can be used as an active medium in optoacoustic ultrasound generators. Keywords: hybrid material, ultrasound generator, nanoparticle, polymethyl methacrylat.

Influence of Metal Gear Tooth Geometry on Load and Wear within Metal-Polymer Gear Pairs

Gear pairs made of the material pairing metal-polymer provide advantages, such as a reduced weight, beneficial damping properties and the possibility to be operated in dry running conditions. However, the service life of the pairing is limited due to wear. The properties of the metallic gearing have a significant influence on the wear behavior of the material pairing. From previous investigations, the influence of the surface topography and the flank hardness of the metal pinion is known. With regard to resource saving and efficient manufacturing of the metal pinion, cold forging offers benefits. Through cold forging, metallic gears for the material pairing can be produced ready-to-use in a process suitable for serial production. In order to enable manufacturing by extrusion, the application of gear radii is necessary. The gear radii significantly affect the extrusion process and the achievable gear properties. However, the influence of gear radii on wear within the metal-polymer material pairing has not yet been investigated. Within this contribution, the influence of the gear radii on the contact behavior as well as the resulting local load and wear of the tooth flank is determined. For this purpose, wear tests with aluminum (AlMgSi1) and steel (16MnCr5) gears with different gear radii within the pairing with polyamide (PA66) gears were performed. It has been shown that the local wear of the tooth flank can be attributed to the local load and that adjusted gear radii lead to a varying load and wear of the metal and polymer gears. Based on the findings, functional relationships regarding the choice of gear radii and the wear behavior are derived which can be applied in the design of cold forged gears.

Ferrite application as an electrochemical sensor: A review

Nano-ferrites are one of the extensively explored sensing materials for the detection and quantification of the evolution of toxic gases from industries, vehicle exhaust and biological wastes. It can be further utilized for the monitoring and regulation of environmental pollution. This review article reports the literature available on ferrite with single metal ion dopant, mixed ferrite materials (multi-ion doping), ferrite-based composites with another metal oxide, polymer and carbon material /ferrite-based core-shell structures. It is reported that the ferrite with a single metal ion dopant exhibits a better response for gas sensing than pure Fe 3 O 4 . Also, by doping the La ions in Mg-ferrite the sensitivity increases many times at lower operating temperature and similar is the case with Ce ion doping to Co-ferrite. Nanocomposite of PANI (Polyaniline) with Cu-ferrite reports higher response for NH 3 gas at room temperature than pure Cu-ferrite and the selectivity of NiO/Ni-ferrite changes for HCHO than the pure Ni-ferrite. In general, ferrites possess characteristic porosity, physical and chemical absorption properties which are easily optimized by choosing appropriate synthesis routes and parameters like pH of the solution, temperature, sintering temperature, nature and concentration of doping/co-doping ions, nano-composites and morphology. This paper consolidates the available literature over the last three decades on the development of ferrites as a gas sensing material. • Ferrites with single metal ion dopant exhibits better response for the gas sensing than pure Fe 3 O 4 . • Nano-ferrites are one of the extensively explored as a sensing material. • By introducing the La ions in Mg-ferrite increases the sensitivity many times. • Nanocomposite of PANI with Cu-ferrite reports higher response for NH 3 gas at room temperature.

INVESTIGATION OF THE LATEST COATINGS WITH SHIELDING PROPERTIES OF ITS OWN PRODUCTION

In the modern world, protection against the influence of man-made electromagnetic fields shielding will be increasingly used. In the transition to international standards (in various industries) in the manufacture of the latest facing and finishing materials, the most promising and demanded building materials with shielding properties. Reducing weight due to the thickness of the shielding coating of building material is not always expedient and is not always allowed by the relevant state and international sanitary norms. Theoretical calculations on this issue or mathematical forecasting minimize the cost of manufacturing the substance of the shielding material, and in general, reduce the total number of measurements to their confirmation. The presented methodology enables to predict protective properties, depending on the parameters of fields that need shielding. The purpose of the study is – the manufacture of the latest coatings of composite structures to predict the protective properties of building materials in a wide frequency range. Methods and methods of research – improvement of the development of a new shielding material by producing metal-polymer material for shielding physical fields and developing a technology for increasing the distribution of shielding particles in the body of a polymeric material (matrix), preventing particle adhesion and increase their dispersion.

ОЦЕНКА НЕСУЩЕЙ СПОСОБНОСТИ СОСТАВНОЙ КОНСТРУКЦИИ САМОЛЕТА, СОСТОЯЩЕЙ ИЗ МЕТАЛЛОПОЛИМЕРНОГО КОМПОЗИЦИОННОГО МАТЕРИАЛА И КЛАССИЧЕСКОГО МЕТАЛЛА

The requirements for modern models of aviation equipment are constantly increasing, as a result of which it is necessary to look for new ways to solve the assigned engineering tasks through the use of new materials, new principles of manufacturing and assembly, as well as through an extraordinary approach to the design of the design of modern aircraft products. In this paper, the engineering methodology of power calculation and design of composite aircraft structures combining metal-polymer composite materials and metal materials is considered. As a composite structure under study, a fragment of an aircraft wing panel is considered, including a stringer made of a traditional structural material (metal) and a metal-polymer composite material skin attached to it. Metal- polymer composite material is a layered material consisting of metal sheets and layers of polymer composite material. Previously, in [1], the characteristics of the stress-strain state (SSS) of a single metal-polymer composite material and each layer in its package were investigated. In this paper, analytical and graphical dependences of the stress state of the elements of a composite structure on their ultimate deformations are obtained. The parameters of the composite panel of the wing, working on tension, and their effect on the stress-strain state, safety margin and load-bearing capacity are investigated. The obtained graphical dependences can be used for a preliminary assessment of the strength of an element of a composite structure at the stage of working out the design concept of an aircraft airframe assembly using a metal-polymer material.

Surface metallization of PET sheet: Fabrication of Pd nanoparticle/polymer brush to catalyze electroless nickel plating

Electroless nickel plating provides a rapid and low-cost approach to prepare surface-metallization material, but complicated technology would increase cost and restrict its application. In this work, a new kind of Pd nanoparticle/polymer brush (Pd/PB) catalytic solution (AS) with a mixture of deionized water, ethanol, 3-aminopropyltriethoxysilane (KH550), PdCl2 solution was designed to modify and activate polyethylene terephthalate (PET) simultaneously. Pd nanoparticle could be adsorbed by PB with –NH2, Si–O–Si groups from hydrolyzed KH550. An activated layer with Pd/PB structure established on PET surface after coating AS solution. The generated Ag/PB that served as seed to catalyze the electroless nickel plating. As a result, a facile route for electroless nickel plating was achieved. The maximum effective thickness, rupture work and adhesion of Ni-plated coating were about 0.8 μm, 0.4 J/m2, and 5B, respectively, and it maintained considerable conductivity even after 1000 times of cyclical bending. This dependable technology has great potential application in the preparation of metal-polymer material.

ПРОЕКТУВАННЯ КОМПОЗИТНИХ МАТЕРІАЛІВ НА ОСНОВІ ДРІБНОДИСПЕРСНОЇ ЗАЛІЗОВМІСНОЇ СУБСТАНЦІЇ ДЛЯ ЕКРАНУВАННЯ ІОНІЗУЮЧИХ ВИПРОМІНЮВАНЬ

На основі аналізу механізмів розсіювання іонізуючих електромагнітних випромінювань та залежності ослаблення випромінювання від порядкового номера елемента та його густини зроблено висновок про можливість їх екранування матеріалами з вмістом заліза. Запропоновано засади проектування композиційного металополімерного матеріалу для зниження інтенсивності рентгенівського та гама-випромінювань. Показано, що зміна поглинання іонізуючого випромінювання зі зміною довжини хвилі випромінювання відбувається немонотонно. Тому для проектування матеріалу необхідно з’ясувати переважні довжини хвиль (частоти) випромінювання, яке потребує екранування. Встановлено, що для ефективного екранування випромінювання існує критична концентрація металевих частинок у полімерній матриці. Це відбувається на порозі протікання електричного струму за вмісту екрануючої субстанції 11−12 % (за вагою). Це добре узгоджується зі співвідношеннями електродинаміки суцільних середовищ. При проектуванні матеріалу з використанням залізорудного концентрату слід враховувати його різні властивості у залежності від виробника. Проектуванню захисного матеріалу повинні передувати лабораторні дослідження з визначення переважної фракції залізорудних частинок за розмірами та вмісту заліза і його сполук у вихідній сировині.

Development and study of protective properties of the composite materials for shielding the electromagnetic fields of a wide frequency range

Composites were shown to be the most promising materials for protection against electromagnetic fields. A technology of magnetic treatment of textile material with magnetic fluid and technology of ultrasonic treatment of a mixture of latex and iron ore concentrate has been developed. This has increased saturation of fibers of the textile material with magnetic fluid nanoparticles, dispersity of the iron ore concentrate, and isotropy of the liquid metal-polymer material. As a result of the use of this technology, the consumption of magnetic fluid for the treatment of the textile material decreased from 45‒50 g/m2 to 35 g/m2 with an improvement of shielding properties. It has been experimentally established that one layer of metal-textile material reduces the magnetic field of industrial frequency by 6 times and the electric field of industrial frequency by 1.5 times. Corresponding figures for the metal-polymer material were 3 and 2. It was found that an electromagnetic field with a frequency of 2.45 GHz is reduced 3.6 times by the single-layer metal-textile material and 5.7 times by the metal-polymer material. It was shown that the metal-textile material with such properties is suitable for the manufacture of personal protective means for personnel operating electrical and radio transmission equipment. Metal-polymeric material is suitable for the manufacture of collective protective means. A calculated evaluation of the effectiveness of protective materials was proposed. It is based on determining the shielding factors of structures of standard shapes. This enables the determination of electrophysical and magnetic properties of the material and their use in the development of protective materials with required shielding factors. The necessity of optimization of shielding factors under conditions of simultaneous influence of electromagnetic fields of heterogeneous sources was substantiated

Effect of Laser Processing on the Qualitative Parameters of Protective Abrasion-Resistant Coatings

The wear of centrifuge screws, common components in industrial and municipal wastewater treatment plants, is studied. The TN-20 tungsten-free hardmetal serves for protecting screw flights against abrasive wear. The 12Kh18N10T steel is primarily used in the manufacture of centrifuge screws. A combined technique of depositing protective wear-resistant coatings is proposed. The technique includes electrospark deposition of a T15K6 hardmetal electrode, application of a metal polymer material (MPM), and final laser processing. To reinforce the MPM, small portions of a VK6 hardmetal mixture were added to a two-component epoxy system filled with ferrosilicon and thoroughly stirred. The reinforcement content was ~60%. This technique produces coatings up to 600 μm thick, with 7.3–10.0 GPa microhardness and 100% continuity. Abrasive water jet tests of the 12Kh18N10T steel samples with protective coatings show that their wear resistance is 7.5 times higher than that of the uncoated samples.

Estimation of strength parameters of small-bore metal-polymer pipes

The paper presents results from a set of laboratory studies of strength parameters of small-bore metal-polymer pipes of type TG-5/15. A wave method was used to estimate the provisional modulus of elasticity of the metal-polymer material of the pipes. Longitudinal deformation, transverse deformation and leak-off pressure were determined experimentally, with considerations for mechanical damage and pipe bend.

Improvement of integrated technology for restoring surfaces of steel and iron parts

There have been proposed new technical solutions including operations of applying coatings onto worn surfaces of steel and cast iron parts by electro-erosive alloying method (EEA). In this case, the EEA coatings are applied in two stages. At the first stage, there is applied a layer on the conditions providing the greatest thickness and continuity of the surfaces obtained. At the second stage, the operation is performed by the same electrode and on the conditions of the discharge energy and productivity corresponding thereto, which provide for the formation of the surface having a roughness value being about 2-4 times higher than that at the previous stage. At least one layer of a metal polymer material (MPM) is applied on the surface formed by the above said EEA method, with this layer having been reinforced by at least one wire reinforcement layer before polymerization.

ОБЕСПЕЧЕНИЕ ТРЕБУЕМОЙ ШЕРОХОВАТОСТИ ПОВЕРХНОСТЕЙ ИЗДЕЛИЙ ИЗ МЕТАЛЛОПОЛИМЕРА НАПОЛНЕННОГО АЛЮМИНИЕМ ПРИ ОБРАБОТКЕ ШЛИФОВАНИЕМ

Currently, machine-building enterprises are increasingly using new composite materials for the production of parts, accessories and repair. One such material is a metallopolymeric composite structure with an aluminum filler. In general, it is an epoxy-dienoic filled with an aluminum matrix excipient. Owing to its flow properties in the uncured state, and hardness and heat resistance when cured, the material is increasingly used in the production. Previous studies have shown the use of metal-polymer material as the material forming the mold parts, as this significantly reduces the cost of equipment for molding plastics. Unlike steel machining modes metallopolymers insufficiently studied, because the material is new, and as yet only finds its field of application. However, in the manufacture of it forming tooling molds required to appoint such process steps and processing modes, which will provide the required dimensional accuracy and surface roughness detail. For a given parameter surface roughness of a metallopolymeric in the processing of grinding was found model of the surface roughness of the parameter rate table movement and the depth of cut.

A Review of Thermal Spray Metallization of Polymer-Based Structures

A literature review on the thermal spray deposition of metals onto polymer-based structures is presented. The deposition of metals onto polymer-based structures has been developed to enhance the thermal and electrical properties of the resulting metal-polymer material system. First, the description of the thermal spray metallization processes and technologies for polymer-based materials are outlined. Then, polymer surface preparation methods and the deposition of metal bond-coats are explored. Moreover, the thermal spray process parameters that affect the properties of metal deposits on polymers are described, followed by studies on the temperature distribution within the polymer substrate during the thermal spray process. The objective of this review is devoted to testing and potential applications of thermal-sprayed metal coatings deposited onto polymer-based substrates. This review aims to summarize the state-of-the-art contributions to research on the thermal spray metallization of polymer-based materials, which has gained recent attention for potential and novel applications.

Using the Hot Embossing Technology to Fabricate the Movable Component on Polymer Material

It presented a novel manufacturing method that was derived from traditional hot embossing technology to fabricate actuators on polymer material in this paper. The conventional photolithography technology, electroplating, and hot embossing technology were utilized in this process. The plastic deformation properties of thermoplastic polymers were main concept. The metal layer deposited on the silicon wafer could be embedded into the polymer substrate by hot embossing technology as temperature being above Tg. When the polymer substrate temperature was cooled below the Tg, the polymer is to de-embossing and remove silicon wafer. The metal layer was transferred from silicon wafer to be embedded in the polymer substrate. Owing to the adhesion between the metal layer and polymer material was more than the metal layer and silicon wafer. For instance, the PMMA was employed as the polymer substrate to fabricate the cantilever beam actuator using the novel technology. Finally, the beam was driven by electrostatic force through 25volts of DC power.

A self-lubricating metal-polymer material for prosthesis friction units

A self-lubricating metal-polymer material for prosthesis friction units