Tensile and Wear Behavior of Calotropis Gigentea Fruit Fiber Reinforced Polyester Composites

AbstractAn experimental study has been carried out to investigate the tensile and wear characterization of polymer composites made by reinforcing Calotropis Gigentea fruit fiber as a new natural fiber into a polyester resin. The Calotropis Gigentea fibres extracted by manual processes have been used to fabricate the composites. The composites are fabricated up to a maximum volume fraction of fibre of 0.35. The tensile strength increased with increase in fiber content. Further, the wear behavior of the Calotropis Gigentea fruit fiber composite were studied with increase in fiber content

Metal nanoparticle‐hydrogel nanocomposites for biomedical applications – An atmospheric pressure plasma synthesis approach

The development of multifunctional nanocomposite materials is of great interest for various biomedical applications. A popular approach to produce tailored nanocomposites is to incorporate functional nanoparticles into hydrogels. Here, a benign atmospheric pressure microplasma synthesis approach has been deployed for the synthesis of metal and alloy NPs in‐situ in a poly (vinyl alcohol) hydrogel. The formation of gold, silver, and gold‐silver alloy NPs was confirmed via spectroscopic and microscopic characterization techniques. The properties of the hydrogel were not compromised during formation of the composites. Practical applications of the NP/PVA nanocomposites has been demonstrated by anti‐bacterial testing. This establishes AMP processing as a viable one‐step technique for the fabrication of NP/hydrogel composites, with potential multifunctionality for a range of biomedical applications

Optimization of machining parameters in drilling hemp fiber reinforced composites to maximize the tensile strength using design experiments

385-390<span style="font-size: 9.0pt;mso-bidi-font-size:11.0pt;letter-spacing:.2pt;mso-bidi-font-style:italic" lang="EN-US">Natural fiber composites today are replacing synthetic fiber composites due to superior properties of natural fibers such as low density, high specific strength and modulus, relative nonabrasiveness, ease of fiber surface modification and wide availability. Drilling is often required to facilitate the assembly of the parts to get the final product. However, drilling composite materials present a number of problems such as delamination associated with the characteristics of the material and with the used cutting parameters. The present investigation is an attempt to study the factors and combination of factors that influence the delamination and the tensile strength of the drilled unidirectional hemp fiber reinforced composites using Taguchi and ANOVA analysis and to achieve the conditions for minimum delamination and for maximum tensile strength. The result shows that<span style="font-size:9.0pt;mso-bidi-font-size: 10.0pt;mso-fareast-font-family:" ms="" pgothic""="" lang="EN-US"> <span style="font-size:9.0pt;mso-bidi-font-size:11.0pt;letter-spacing:.2pt; mso-bidi-font-style:italic" lang="EN-US">the feed rate and cutting speed are seen to make the largest contribution to the delamination and tensile strength. Confirmation experiments are conducted to verify the predicted optimal parameters with the experimental results. </span

Wear and Corrosion Behavior of Zr-Doped DLC on Ti-13Zr-13Nb Biomedical Alloy

Zirconium (Zr)-doped DLC was deposited on biomedical titanium alloy Ti-13Nb-13Zr by a combination of plasma-enhanced chemical vapor deposition and magnetron sputtering. The concentration of Zr in the films was varied by changing the parameters of the bi-polar pulsed power supply and the Ar/CH4 gas composition. The coatings were characterized for composition, morphology, nanohardness, corrosion resistance in simulated body fluid (SBF) and tribological properties. X-ray photoelectron spectroscopy (XPS) studies on the samples were used to estimate the concentration of Zr in the films. XPS and micro- Raman studies were used to find the variation of ID/IG ratio with Zr concentration. These studies show that the disorder in the film increased with increasing Zr concentration as deduced from the ID/IG ratio. Nanohardness measurements showed no clear dependence of hardness and Young�s modulus on Zr concentration. Reciprocating wear studies showed a low coefficient of friction (0.04) at 1 N load and it increased toward 0.4 at higher loads. The wear volume was lower at all loads on the coated samples. The wear mechanism changed from abrasive wear on the substrate to adhesive wear after coating. The corrosion current in SBF was unaffected by the coating and corrosion potential moved toward nobler (more positive) values