Development of hybrid magnetorheological elastomers by 3D printing

Waterjet machining has attracted great attention in the conditions of hard-to-machine materials, microstructures, or complicated industrial components, and it has become well-established in all major areas of theoretical researches and already been found across the broad spectrum of technical application areas especially in the specific sectors of scientific frontiers, including the mechanical precision component, advanced functional material, intelligent automotive engineering, aerospace equipment, renewable energy science, leading medical instruments, etc. This paper reviews the historical and latest research developments and integrated applications of waterjet machining in the domains of mechanism and performances, which covers a lot of key aspects such as waterjet machining optimization, dynamic simulation and process monitoring of machining process, and the influence mechanism of waterjet machining as well. Its machining mechanism, performance capability, functional advantages, and inherent disadvantages are characterized and assessed in detail, so that the integrated applications of multifield-assisted waterjet machining can be introduced and focused thereafter. Finally, various future development prospects in all the abovementioned aspects of waterjet machining are discussed systematically and explored subsequently, which contribute to the acquirement of a series of comprehensive conclusions. This review can be used as suitable and effective tools to study and summarize the complicated correlations between waterjet machining mechanism and its actual working performances in different environmental conditions; therefore, this proposed investigation facilitates the precision manufacture or characteristic improvements of industrial product with higher efficiency and better quality in return.

Waterjet machining and research developments: a review

Due to the improvement of the mechanical properties of polymer composite belts used in vacuum belt conveyors, its perforation process causes a lot of technical issues for manufacturers worldwide The objective of this paper is to analyze the belt punching process with two cutting edges and present the influence of the piercing punch shape on the perforation force Based on the analysis, the analytical stress model was derived and validated by using both empirical and FEM tests The application of the proposed model was proved by presenting the methodology used to estimate the perforation force for the flat piercing punch based on the mechanical properties of the belt obtained from simple strength tests (uniaxial tension, compression, and shear), with an error between 4 and 15% In this report, the analysis of the piercing punch profiles was made and eight different piercing punch profiles were tested Presented results confirmed that the spherical bowl punch may be considered as a most effective tool for belt punching, because it reduced the perforation force by 60% and the precision of the created holes was the best among the tested punch profiles for all three groups of polymer composite belts By combining the obtained results, in the form of shape factors β, with the perforation force approximation model, it is possible to calculate peak force value for the specified tool profile and belt type and use this data in the design process of the punching dies

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Estimation of the perforation force for polymer composite conveyor belts taking into consideration the shape of the piercing punch

Punch optimization is important in improving the technological process of belt perforation. Research about this process can rarely be found in the scientific literature. The objective of this paper is to determine the effective geometry of the piercing punches with a spherical bowl used for polymer composite belts. In order to fulfill this goal, the complex research of the influence of the geometrical features of the piercing punch on the perforation force, the hole quality, and the tool life has been conducted. For derivation of the proposed model, the authors have used the combination of analytical and FEM analyses, along with the experimental tests validation. Based on the results, there are clear correlations between the depth of the spherical bowl punch and the perforation force or the hole diameter deviation. By analyzing the ratio of the perforation and transverse force, we are able to evaluate how the tool life will change for different sets of geometrical parameters. All these correlations have been used to derive the indicators of the perforation force, tool life, and hole quality. Based on those, the optimization function has been specified. Finding the minimum value of this function makes it possible to define the optimal tool geometry. The design of effective tools for belt perforation with diameters D = 5, 6, 8, and 10 mm has been presented, but the obtained characteristic makes it possible to find an optimal solution for any diameter which lays in the range from 3 to 10 mm. Since the model has been built based on the indicators, it is easy to adjust it to match any specific requirements of the belt manufacturers, which makes it useful for tool designers.

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Determination of the effective geometrical features of the piercing punch for polymer composite belts

Compressive properties of magnetorheological elastomer with different magnetic fields and types of filler

The determination of mechanical properties of magnetorheological elastomers (MREs)

Perforated belts, which are used in vacuum conveyor belts, can have significantly different mechanical properties like strength, elasticity due the variety of used materials and can have different thickness from very thin (0,7 mm) to thick belts (6 mm). In order to design a complex machine for mechanical perforation, which can perforate whole range of belts, it is necessary to research the influence of the cutting edge geometry on the parameters of the perforation process. Three most important parameters, which describe the perforation process are the cutting force, the velocity and the temperature of the piercing punch. Results presented in this paper consider two different types of punching (a piercing punch with the punching die or with the reducer plate) and different cutting edge directions, angles, diameters and material properties. Test were made for different groups of composites belts – with polyurethane and polyester fabric, polyamide core or aramid-fiber reinforced polymers. The main goal of this research is to specify effective tools and parameters of a perforation process for each group of composites belts.

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Analysis of the influence of the cutting edge geometry on parameters of the perforation process for conveyor and transmission belts

The study of mechanical properties of natural polymers in the compacting process

Abstract The article presents the results of research on the effect of extrusion tube geometry on the axial force being the key parameter of the dry ice piston extrusion process. The tests were carried out with the experimental set-up based on a cylindrical extrusion tube used alone and supplemented with reducer (orifice). The focus of the experiments was to determine the effect of compression tube reducer on the value of the force of resistance FOP in the dry ice compression process. Its value can subsequently be used as the basis for establishing guidelines for designing and building machines for compression and pelletizing of dry ice.

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Ireneusz Malujda

Papers

The determination of mechanical properties of magnetorheological elastomers (MREs)

Estimation of the perforation force for polymer composite conveyor belts taking into consideration the shape of the piercing punch

Analysis of the influence of the cutting edge geometry on parameters of the perforation process for conveyor and transmission belts

The study of mechanical properties of natural polymers in the compacting process

Dry Ice Compaction in Piston Extrusion Process