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Century natural fibers ( Agave americana L.) have superior mechanical properties. For their usage as an effective reinforcement in biocomposites, they require surface modification. In the present study, these fibers were treated with 5% aq. NaOH solution for optimized 1-h period. The effect of alkali treatment on the mechanical, thermal, and morphological properties was been studied. The results indicated thinning and surface roughening of the fibers and removal of hemicellulose on alkali treatment. The tensile strength and elongation at break improved on alkali treatment. X-ray studies indicated increase of crystallinity for alkali-treated fibers.

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Fiber reinforced plastic component (FRP) having complex shaped geometry is prepared by rubber pressure molding (RPM) technique. The technique is based on the matching die set, where the die is made of hard metal like steel and the punch from flexible rubber like materials. The flexible rubber punch intensifies and uniformly redistributes pressure (both operating pressure and developed hydrostatic pressure due to the flexible rubber punch) over the surface of product. The distribution of pressure was analyzed by ANSYS over a processing pressure of 0.5-50 MPa. The analysis was extended to find out the optimum hardness of rubber mold, where the pressure distribution is uniform. For this, analysis was carried out for NR vulcanizates where the loading of carbon black was varied from 0 to 75 phr with an increment of 15 phr. The strain energy density function of 2-, 3-, 5-and 9 parameter Mooney-Rivlin; 1st-, 2nd-, and 3rd order Ogden; Neo-Hookean; 1st-, 2nd-, and 3rd order Polynomial; Arruda-Boyce; 1st-, 2nd-, and 3rd order Yeoh; and Gent were used. 45phr carbon black loading NR vulcanizate shows best result.

Response surface methodology (RSM), Tungsten carbide cobalt composite (WCCo). A B S T R A C TIn this two-part research, a unified approach is presented to model and optimize the electro-discharge machining (EDM) parameters on WC/6%Co using response surface methodology (RSM) and desirability function (DF) concept. In the first part, four controllable parameters, viz., discharge current (A), pulse on-time (B), duty cycle (C), and average gap voltage (D) have been selected as the input variables to evaluate the process performance in terms of material removal rate (MRR), tool wear rate (TWR), and arithmetic mean surface roughness (Ra) as the performance characteristics. The modeling phase begins applying face-centered central (FCC) composite design to plan and analyze the experiments in accordance with the RSM. For every response, the significant forms of influential parameters were properly identified conducting a comprehensive analysis of variance (ANOVA) at 1, 5, and 7% level of significance. It has been revealed that all the direct effects of input parameters are extremely momentous affecting both the MRR and TWR. Moreover, the pure quadratic effect of duty cycle (C 2 ), the reciprocal effects of discharge current with pulse on-time (A×B), duty cycle (A×C), and gap voltage (A×D), as well as the interaction amongst the pulse on-time with duty cycle (B×C) were also reached to be important terms affecting the MRR. The TWR measure behaves the same way, however, it exhibits a more nonlinear mathematical form containing the second order effect of discharge current (A 2 ) as an additional important term. On the other hand, for the Ra, the only significant parameters are the main effects of the first two inputs (A and B) plus the interactions of current with pulse on-time (A×B) and with gap voltage (A×D). The results indicate that the suitably proposed step-by-step implemented approach can substantially elucidate the highly multifaceted behavior of the chosen grade WC-Co under different EDM conditions providing a reliable platform to both navigating the operational region and seeking for optimal working circumstances confidently.