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Industrial vacuum cups are used for lifting, holding and moving a wide variety of automated applications for handling semi-finished products and parts made of a wide range of materials - metal, glass, plastic, paper, wood, etc. and are used in a variety of industries. This paper presents some of the authors` theoretical and experimental research on the maximum lifting force that different types of vacuum cups can achieve. The study was carried out on the basis of sizing recommendations made by manufacturers and dealers of these types of vacuum cups. The specially designed experimental stand was installed on the universal material testing machine LBG 100 kN and allowed the practical determination of these lifting forces provided by various types of industrial vacuum cups. Lifting force measurements were carried out with the AXIS FB 1k digital dynamometer attached to the machine. Vacuum cups of 3 different shapes and made of 3 different materials were used, using different vacuum depressions - 0.3 bar, -0.5 bar, -0.7 bar and -0.9 bar. The research aimed to determine by measurement the maximum lifting force of these types of vacuum cups applied to steel parts. The results obtained for these forces were compared with the calculated theoretical values, with the manufacturer’s recommended dimensioning values, and comparative conclusions were also drawn on the maximum lifting force provided by the different types of industrial vacuum cups studied.

The use of digital technology has become a useful and also a preferred process in the realization of dental prosthetic restorations, because through it, superior quality dental prostheses are obtained in terms of aesthetics, accuracy of execution and durability. CAD/CAM technology is changing all aspects of dentistry, making dental restoration processes much easier and more efficient for dentists, patients and dental technicians. The materials that can be used to manufacture dental restorations designed using Exocad software depend on the type of restoration (crowns, bridges, veneers, etc.) and the manufacturing method (milling with a 3-, 4-, or 5-axis CAM device); available materials include: PMMA (polymethyl methacrylate) and zirconia. Using digital technology, in this study we performed 6 fixed prosthetic restorations, of which 5 unidental restorations (5 dental crowns) and 1 pluridental restoration (a 4-element dental bridge); of the 6 prosthetic restorations, 3 restorations will be fixed by cementing on dental abutments, and 3 restorations will be fixed by screwing on implants. Digital technology allows the use of higher quality materials, resulting in more resistant and more aesthetic prosthetic restorations; helps reduce the occurrence of errors; obtaining a better marginal adaptation and a perfect adaptation to the anatomical structures of the patient`s teeth.

Biodegradable bio composites with potential applications in medical implants were prepared with starch content by in situ polymerization technique using polyurethane prepolymers. (PU) and acrylamide (AAM) monomers. The structure and properties of bio composites were evaluated. FT-IR spectroscopy showed bonding between N=C=O functional group terminated polyurethanes confirmed improved compatibility of prepolymers, AAM, starch and bio composites. The DSC data are the glass transition (Tg) of the bio composite and ordinary polyacrylamide (PAAM) network. By incorporating starch and polyurethane in the form of an interpenetrating network into a polyacrylamide network, mechanical and thermal properties of bio composites due to higher crosslink density given by hard segment content. We studied the swelling behavior of both bio composites and individual PAAM networks under different pH conditions to validate their biocompatibility and potential use in biomedicine setting. The hydrolytic stability of biocomposites and PAAM networks was investigated using phosphate buffer. Hydrolytic stability of biocomposites was found to be higher comparison with PAAM network. Morphological analysis of the samples showed uniform distribution and good interfacial adhesion. Improves sample biodegradability it was revealed by the soil runoff test.

The materials of the given article are devoted to the problem solution associated with one of the processing plastic waste methods by adding various fillers in order to obtain the final product for the thermal insulation materials manufacture. The researches were conducted using the UPR (unsaturated polyester resin) samples made of EPS (expanded polystyrene) plastic waste and crushed recycled polyethylene from greenhouse film waste with various types of wood waste from carpentry workshops. The tests have revealed that when EPS is added to the unsaturated polyester mixtures, the EPS thermal conductivity coefficient decreases with a slight decrease in density, which gives the wide opportunities to use EPS waste as an additive for UPR and expands the ways of its potential industrial application, and the addition of styrene to the compositions containing 10% of styropor causes a clear decrease in thermal conductivity characteristics and a slight decrease in the density of these mixtures. The values of the thermal conductivity coefficient and the density of the low-density polyethylene material increase with the wood powder percentage raising used as an organic filler.

Main goals like technical innovation, costs and respect for the environment urge us to discover finer, lighter, biodegradable, and more «intelligent» materials in their functionality. The development of industrial design is motivated by criteria such as the environment, sustainability, the need for lightweight products, manufactured with fewer components and integrating various functions. As experts in new materials and technologies for the development of innovative products, we work closely with international research institutes as part of our projects. We want to create materials that combine such properties in the most efficient way, interacting with their close environment and the environment in general and, based on their features, to be transformed through various processes in completely different materials. The goal of our work is to compare different existing materials with a new bio-based material using quantifiable measurement indicators and sensory measurement indicators. The purpose of this article is to provide a few elements that can be used as a guide in establishing a quantitative impact assessment strategy based on the use of sensory evaluation techniques. In the framework of our presentation, we will focus mostly on comparing the materials via a metrological tool for quantifying tactile characteristics likely to be correlated to the `ground truth` that constitutes a sensory profile.

Can polymer-infiltrated florapatite glass ceramic produced from waste materials, such as clam shell and soda lime silicate glass, be used in prosthetic rehabilitation? The purpose of this study is to investigate the effect of Si/Ca ratio on the mechanical properties of Nb-Bi-Ce doped polymer-infiltrated fluorapatite ceramic networks (PICNs) produced from clam shell (CS) and soda lime silicate (SLS) glass by conventional melt-quench technique, used as a dental ceramic. PICNs comprising Si/Ca at four different weight percentage ratios: 1.27% (PICN-1), 2.15% (PICN-2), 4.12% (PICN-3) and 12.6% (PICN-4) were prepared (n=10). The powder mixtures in four different ratios were compressed in a rectangular prism shaped mold and subjected to equal pressure from all sides in a cold isostatic press, followed by heat treatment at 750C for 3 h. Then complete vacuum infiltration was done with a polymer mixture then low temperature firing was applied leading to the formation of the PICNs. Wear behavior and 3-point bending properties were evaluated and specimens were analyzed using scanning electron microscopy (SEM). The friction and wear properties were determined by means of a pin-on-disk tribotester. Since the flexural strength test did not show normal distribution, Kruskal Wallis test was performed in independent groups, p[0.05. There is a significant difference of flexural strength values between the groups (p=0.032), it was determined that the difference was between the PICN-1 and PICN-4 groups (p=0.037). In the analysis of wear scar, abrasion grooves were also observed. The results of this study showed that high Ca and Si content in CS and SLS glass, respectively, encourages the use of waste materials in the production of PICNs intended to be used in prosthetic rehabilitation. The composition of PICNs produced from waste materials affected flexural strength and wear behavior. Increasing the Si/Ca ratio was found to support the mechanical properties of experimental PICN and that experimental PICNs can be considered as high potential candidates for dental applications.

The study establishes a theoretical evaluation trough several models concerning the dielectric properties of some new eco-composites made of a cellulosic derivative matrix – hydroxypropyl methylcellulose (HPMC) – in which distinct sorts of fillers (ceramic, metallic and bio-derived) were introduced. The investigation describes the impact of the filler addition on the dielectric constant, the dielectric breakdown, and finally how these two factors are contributing to the electric energy density of purposed eco-composites. After incorporation of the reinforcement agents, the dielectric constant significantly increases comparatively with the matrix, as a function of the type of filler used. Moreover, by assessing of the dielectric breakdown, it is observed that with the increase of filler quantity, this parameter slightly decreases for all samples. The data concerning the electric energy density reveal that, by filler insertion in the HPMC matrix, an improvement occurs, especially for the barium titanate system owing to its large dielectric constant. These data are promising for design of new eco-composites having improved dielectric features as demanded for green energy storage devices. Since the materials have biodegradable and biocompatible character, they also have importance in bio-related applications.

The industrial grade hollow beads were divided into three particle sizes of 40 mesh, 60 mesh and 80 mesh and added into the epoxy resin material matrix to prepare porous foam composites. The quasi-static compression experiments were performed on porous foam composites at room temperature, and the stress-strain curves of quasi-static compression processes were analyzed separately for different particle sizes. According to the characteristics of the compression curve of porous foam materials, the representative characteristic parameters of each stage are extracted separately. The fracture characteristics of the microscopic samples of the compressed material specimens were observed by electron microscopy, and the deformation patterns of the composite materials were analyzed. And combined with SEM pictures to analyze the form of microbead crushing and matrix pore collapse mode, according to which the particle size suitable for this matrix is 60 mesh and the mass fraction of microbeads is 10%.

Polyethylene (PE) materials have been widely used in industrial and living fields such as natural gas pipelines, drainage pipes, sewage pipes. Punch test is an interesting tool for studying the mechanical properties of materials. However, the deformation behavior involved in punch test is complicated, it is, therefore, essential to investigate the influence of punch test conditions on the mechanical properties of PE materials. Punch tests have been carried out on PE specimens with different punching speed (0.01, 0.1, 1, 10 and 100mm/min) and different punch head diameters (4, 6, 8 and 10mm). The experimental results show that the maximum load from the load-displacement curve increases with the increase of the punch head diameter under the same punch speed. When the punch speed is slow, the force-displacement curve of PE specimens contains four typical stages, namely, elastic stage, yield stage, strain softening stage and strain hardening stage. However, the PE specimen breaks before reaching the strain hardening stage when the punch speed is fast. Similarly, the maximum load increases with the increase of punch speed when the same punch head diameters are used. Furthermore, a three-dimensional finite element (FE) model of PE specimens subjected to punch load has been established to further analyze the deformation and failure behavior. A good agreement between the simulation results and the punch test data is achieved.

To analyze the implant overdentures components as following: morphology and composition aspects of several small diameter systems, evaluating both the implant and the retention system (1); biomechanical characteristics of some of the polymers used for manufacturing the overdenture base (2). An experimental in vitro study was carried out through optic microscopy to analyze the metallic structure of dental implants components and anchor systems. The marketed products analyzed were mini1SKY (Bredent) and 3M ESPE MDI Mini dental implant (3M ESPE). A Zeiss microscope with Kohler illumination was used. Samples from polymeric materials commonly used for overdenture based (i.e. Duracryl and Superacryl) were analyzed by 3 point bending test by Tira device. In the case of the mini1SKY system (Bredent), the dental implant has the typical structure of marketed pure titanium that went through thermomechanical processing, resulting in a higher rate of granulation, and the matrix has a completely different structure, as it is a monophasic structure specific to materials that crystalize in the cubic system of the stainless steels. In the case of the 3M ESPE MDI system, the implant and the matrix have a similar microstructure, specific to a Ti-6Al-4V beta alloy annealed with an extremely fine rate of granulation. Duracryl and Superacryl samples fractured variable (frequently close to the midline) and were similar in regard to the value of breaking force. Knowledge of the materials of the components of implant overdenture guide their selection from the point of view of biocompatibility, resistance and ensuring denture retention.