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Environment is being polluted day by day due to intensive use of synthetic fiber as reinforcement for polymer composite. The researchers, engineers and scientists are showing their interest in natural fiber as reinforcement in place of synthetic fiber due to its green nature. In this work, short sisal fiber reinforced epoxy composites were manufactured by hand lay-up method at 30% wt. of fiber loading and fiber length used was 10 mm. The parameters taken were load, speed and sliding distance. Load was taken as 10, 15, 20, 25 and 30 N, Sliding speed as 1 m/s, 2 m/s and 3 m/s and Sliding distance as 1000 m, 2000 m and 3000 m. The wear properties (specific wear rate and coefficient of friction) of prepared composites are carried out. All tests are performed as per ASTM standard. On increasing the load, sliding velocity and sliding distance, the specific wear rate is found to increase whereas value of coefficient of friction decrease.

In this investigation, biodegradable composites were fabricated with polycaprolactone (PCL) matrix reinforced with pine cone powder (15%, 30%, and 45% by weight) and compatibilized with graphite powder (0%, 5%, 10%, and 15% by weight) in polycaprolactone matrix by compression molding technique. The samples were prepared as per ASTM standard and tested for dimensional stability, biodegradability, and fracture energy with scanning electron micrographs. Water-absorption and thickness-swelling were performed to examine the dimensional stability and tests were performed at 23 °C and 50% humidity. Results revealed that the composites with 15 wt % of pine cone powder (PCP) have shown higher dimensional stability as compared to other composites. Bio-composites containing 15–45 wt % of PCP with low graphite content have shown higher disintegration rate than neat PCL. Fracture energy for crack initiation in bio-composites was increased by 68% with 30% PCP. Scanning electron microscopy (SEM) of the composites have shown evenly-distributed PCP particles throughout PCL-matrix at significantly high-degrees or quantities of reinforcing.

A better understanding of material deformation behaviours with changes in size is crucial to the design and operation of metal microforming processes. In order to facilitate the investigation of size effects, material deformation behaviours needed to be determined directly from material characterizations. This study was aimed at the design and manufacture of a compact universal testing machine (UTM) compatible with a 3D laser-confocal microscope to observe the deformation behaviour of materials in real-time. In this study, uniaxial micro tensile testing was conducted on three different thin (0.05 mm, 0.1 mm, and 0.3 mm) copper specimens with characteristic dimensions at micro scales. Micro tensile experimental runs were carried out on copper specimens with varying grain sizes on the newly developed apparatus under a 3D laser-confocal microscope. Microscale experiments under 3D laser-confocal microscope provided not only a method to observe the microstructure of materials, but also a novel way to observe the early stages of fracture mechanisms. From real-time examination using the newly developed compact testing apparatus, we discovered that fracture behaviour was mostly brought about by the concave surface formed by free surface roughening. Findings with high stability were discovered while moving with the sample grasped along the drive screw in the graphical plot of a crosshead’s displacement against time. Our results also showed very low mechanical noise (detected during the displacement of the crosshead), which indicated that there were no additional effects on the machine, such as vibrations or shifts in speed that could influence performance. The engineering stress-strain plots of the pure copper-tests with various thicknesses or samples depicted a level of stress necessary to initiate plastic flowing inside the material. From these results, we observed that strength and ductility declined with decreasing thickness. The influence of thickness on fracture-strain, observed during tensile testing, made it clear that the elongation-at-break of the pure-copper foils intensely decreased with decreases in thickness. The relative average surface-roughness Ra was evaluated, which showed us that the surface-roughness escalated with the increasing trend of plasticity deformation (plastic strain) ε. For better understanding of the effects of plastic strain on surface roughness prior to material fractures, micro tensile tests were performed on the newly developed machine under a 3D laser-confocal-microscope. We observed that homogeneous surface roughness was caused by plastic strain, which further formed the concave surface that led to the fracture points. Finally, we concluded that surface roughness was one of the crucial factors influencing the fracture behaviour of metallic sheet-strips in metal microforming. We found that this type of testing apparatus could be designed and manufactured within a manageable budget.

Polycaprolactone (PCL) was reinforced with natural fibres as they not only permit a substantial reduction of the material costs, but also play a role as reinforcement in mechanical properties. This work was focused on the estimation of mechanical and thermal behaviour based on PCL and Pine Cone particles (PCP) filler at different weight percentages (0, 5, 10, 15, 30 and 45 wt%). Tests results indicated considerable improvement in mechanical properties, corresponding to a gain in impact strength and % elongation of 6 and 9.2% at 15 wt% particle loading, respectively. Some decrease in thermal stability was observed for composites with increasing filler content where as composite at 15% PCP was not significantly affected. Lower melting and crystallization enthalpies and higher crystallinity values were obtained for bio-composites compared with neat PCL. Some decrease in thermal stability and increase in oxygen and water vapour barrier properties were also observed for composites with increasing filler content.

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