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This paper presents a characterization of PA6 and the blend PA6+EPDM (60/40) by tensile tests in order to evaluate several mechanical properties for impact resistance applications. Results were found to be dependend on test rate (10 mm/min, 250 mm/min and 1000 mm/mm). SEM investigation point out a homogenous structure. The blend has better value of energy at break, for the higher test speed: for v=250 mm/min this characteristic has the value of energy at break 29.7 J and the blend has 76.3 J. At 1000 mm/min, PA6 has this charcateristic of 20 J, but for the blend, it is almost insensitive for the two higher test speeds (76.3 J at 250 mm/min and 72.4 J at 1000 mm/min, respectively) as compared to the neat polymer that decreases this feature when thr test spee increases. At the lowest teste speed, the values of energy at break for the materials in this study are close (90.2 J for PA6 and 87.7 J for the blend). The results from tensile tests pointed out that the formulated blend is recommended for impact resistance applications.

Recycling is a key process in any sustainable development strategy. This paper proposes solutions for the increasing waste collection rates by developing an educational model for developing innovative waste management solutions. The focus in this paper will be on making the correlation between experimental studies on compressive properties of recycling waste and designing a smart waste management compactor. Based on previous achievements on developing an innovative compactor system with selective waste collection, actual experimental trials will be analysed for generating compression patterns for different types of common waste containers which will be used in the conceptual design process of a compactor, impacting concept definition of all 3 subsystems: mechanical, electrical and software. A dedicated software module for compression parameters will be developed for importing experimental data trials and based on these to process and identify relevant compression parameters defining compression pattern for different common waste containers. These parameters will be used to assist the wok mode state machines for compacting wastes. This will improve compactor performance by optimization of compactor usage smart adaptability.

This paper describes the mechanism and trend of High gloss polymer compounds replacing of paintable plastic parts in automobile industry, and gives some solution overcoming the appearance defects that Painting free parts form easily flow marks and Weld lines in injection molding.

This paper presents a new basic nonlinear track model consisting of an infinite Euler-Bernoulli beam (rail) resting on continuous foundation with two elastic layers (rail pad and ballast bed) and intermediate inertial layer (sleepers). The two elastic layers have bilinear elastic characteristic obtained from the load-displacement characteristic of the rail pad and ballast. A time-varying load with two components - time-constant one and harmonic other, representing the wheel/rail contact force is considered as the track model input. Rail deflection due to the time-constant component of the load is obtained solving the nonlinear equations of the balance position. Subsequently, the structure of the nonhomogeneous foundation is determined. Dynamic rail response in terms of receptance due to the harmonic component of the load is calculated using the linearised track model with nonhomogeneous elastic characteristic. Influence of the time-constant component and the reflected waves due to the nonhomogeneous foundation are presented.

The main objective was to reduce the consumption of material when obtaining 3D printed parts (different empty shapes inside) and the secondary one was to maintain the mechanical properties closer to the full printed version. In order to achieve these objectives, two internal configurations were designed - a configuration with hexagonal gaps (material reduction was 30%) and a configuration with sinuous gaps (material reduction was 15%). The specimens thus obtained were tested for traction, three-point bending and shock (resilience). Hexagonal hollow configuration has a resistance values close to those of solid specimens but with the advantage of consuming with 30% less material.

Polymethyl methacrylate (PMMA) is one of the common widely accepted biomaterials in prosthetic dentistry due to its acceptable advantages, since 1937. In the present work, PMMA reinforced with Al2O3 nanowires (Al2O3 NWs) and ZrO2 nanoparticles (ZrO2 NPs) were fabricated by a self-curing method. Mechanical and tribological tests were conducted to study the effect of nanofillers on the mechanical and tribological performance of PMMA nanocomposites. Compression and microhardness tests, as mechanical tests, were accomplished to estimate the elastic modulus and microhardness number of the present nanocomposites. Also, tribological properties of unfilled PMMA and its nanocomposites were realized by pin-on-disk tester under dry sliding conditions. Wear test was conducted at room temperature under applied loads of 10, 20, 30, 40, and 50 N at a constant sliding speed and distance of 1.256 m/s and 226 m, respectively to study wear rate and coefficient of friction (COF) of the nanocomposites. Experimental results revealed that the elastic modulus, microhardness, wear rate, and COF were enhanced with increasing nanofiller content up to 0.5 and 0.7 wt. % of Al2O3 NWs and ZrO2 NPs, respectively. Also, wear rate increased with increasing applied loads up to 50 N, while COF decreased with increasing applied loads up to 40 N. Finally, specimens’ worn surfaces were examined and imaged using scanning electron microscope (SEM).

This study presents a Solidworks® Plastics application in a company in the Automotive Industry for the aftermarket of auto parts manufactured by the injection molding process, the focus is on the redesign of an injection vein plate for achieve uniform filling of a 16 cavity mold with a geometry made up of a mixture of natural rubber and two metal components. This work proves that the use of symmetrical commands is not always the best option. The distances between runners were not taken into account as a source of the future wears problems in the mold. A layout is created with a combination of 2D and 3D sketches by turning the injection chanels 180° in the problem cavities to increase the distances between runners and the filling of the 16 cavities is verified by simulation. It is also demonstrated by simulation that increasing the injection point size is not necessarily always the best option for cavity filling.

The recycling of high-density polyethylene plastic (HDPE) plays a crucial role in sustainable development. However, obstacles to the use of recycled HDPE remain because of the material and processing properties and odors of recycled HDPE. The odor of recycled detergent bottle plastic leads to rejection by most detergent manufacturers. Recently, some recycling enterprises have adapted recycling with odor reduction processes involving the use of solvents, antimicrobial additives, and odor extraction units in feeders and extruders. However, these processes may affect the quality and cost of recycled plastic. Most small and medium businesses (SMBs) may not favor these effects due to their limited models and resources. In addition, most SMBs are unwilling to replace their current recycling operation units. Hence, this study aimed to find alternative and economical ways for odor reduction in the recycling process. A modification of the recycling process was introduced in the pretreatment of plastic flakes before entry into the feeder of an extrusion unit. The effect of selected washing temperatures, i.e., 65℃, 75℃, 85℃, and 95℃, on the removal of odor from recycled HDPE was further studied. The addition of sodium bicarbonate, calcium carbonate, and citric acid into a heated water bath enhanced the deodorizing effect. The relationship of these three chemicals with the deodorization of HDPE plastics was investigated through sensory evaluation. Lastly, the potential of the deodorized recycled HDPE for resin pellet production and commercialization were investigated.

The investigation on the effect of adding silane modified chopped E-glass fibre and Aluminium metal wire-mesh into nano silica toughened nylon 6-6 thermoplastic composites on mechanical, drop load impact, fatigue and tribological behaviour is studied in this paper. The primary aim of this research work is to develop a hybrid Nylon 6-6 nanocomposites having high stiffness, toughness and wear resistance. The chopped glass fibre and Al wire-mesh was surface treated with the help of 3-Aminopropyletrimethoxylane (silane) and acid etching. The tensile results revealed that additions of glass fibre and Al mesh into nano - silica toughened nylon 6-6 composite gives improved tensile and flexural strength. Similarly, the Izod impact strength of Al-mesh reinforced nano silica (1vol.%) toughened nylon 6-6 gives superior energy absorption up to 6 Joules/cm. The drop load impact penetration of composite N3 (59% - Nylon 66, 20% - E-glass fibre, 20% - Al wire mesh and 1 % - nano silica) shows very limited penetration than other composites. Highest fatigue life of 16391 cycles was observed for the composite designated N3, which contains 1 vol.% of nano silica, whereas the composite containing 2 vol.% of nano silica gives very lower specific wear rate and Co-efficient of friction. The developed composite which has better modulus, stiffness, wear resistance and fatigue life could be possibly used in automobile power transmission gears, domestic equipment and farm related machineries.

Great interest has been shown lately in bio-composite materials because they are inexpensive and sustainable. Composites with matrices and natural reinforcers have been little studied. Here, we study certain mechanical properties of composite materials with a Dammar-based matrix (also named hybrid matrix) and flax fabric reinforcement. To be precise, we examine three types of resins where Dammar is the major component, with a volume proportion of 55%, 65% and 75%. In this respect, we have made composite materials reinforced by two types of flax fabric and we have measured the characteristic curves and some mechanical properties, such as the Young’s modulus, tensile strength and elongation at break using tensile tests. Based on the obtained properties, it is proposed or possible to use these materials in orthopedics.