Papers by Keyword: Tensile Toughness

Abstract: This study explores the effect of incorporating Brachirus orientalis shell powder as a natural filler on the mechanical and moisture absorption properties of polyvinyl chloride (PVC) paste composites. Composites were formulated with varying filler loadings (1 wt.%, 2 wt.%, and 3 wt.%) and evaluated through tensile testing and water absorption analysis. The results showed that low filler concentrations (1–2 wt.%) maintained tensile strength and ductility close to those of neat PVC, indicating good filler dispersion and interfacial bonding. However, at 3 wt.% filler content, a reduction in tensile strength and Young’s modulus was observed, likely due to agglomeration and microstructural defects. Despite this, engineering and true tensile strains increased with filler loading, reflecting improved toughness and energy dissipation. Furthermore, water absorption decreased with increasing filler content, demonstrating enhanced resistance to moisture ingress due to the barrier effect of the shell particles. These findings support the potential of B. orientalis shell powder as an eco-friendly reinforcement for improving the toughness and environmental durability of PVC composites.

Abstract: Being very strong fibers, carbon nanotubes (CNTs) are excellent choice for various metal matrix composites (MMCs). Many researchers have reported amelioration in mechanical and thermal characteristics of the MMCs driven by CNTs addition. However, the effect of multi-walled carbon nanotubes (MWCNTs) addition on the formability of the MMC is relatively less addressed area. In present study, 0.2 wt. % MWCNTs were added in aluminum matrix using induction melting technique and their effect on the various aspect of metal forming characteristics were studied. Two different type of MMC were prepared i.e., re-melting flux (RM) MMC using re-melting flux and multi-functional flux (MF) MMC using multifunctional flux.The experimental results showed that the MF Flux MMC had ultimate tensile strength 65% more than pure aluminum. An analogous behavior was seen in true stress-true strain characteristics along with necking stress and tensile toughness. Contrarily, the hardening factor, strength coefficient, necking strain and strain rate sensitivity values decreased in case of RM Flux MMC and increased for MF Flux MMC as compare to the pure aluminum. This behavior of the materials could be attributed to the process variation used for the incorporation of nanotubes in aluminum matrix.

Abstract: In the current study, consequence of ECAP on the toughness characteristics of the Al-Zn-Mg alloys was studied. Three set of Al-Zn-Mg alloys (5, 10 and 15% Zn and 2% Mg) were selected and ECAPed. Also, consequence of zinc on the toughness characteristics of the alloy, before and after ECAP was studied. After ECAP, grain size of the alloys decreased and significant rise in the strength and ductility of the alloys were noticed. Mainly, modulus of toughness of the alloys increased with successive ECAP passes. But, the modulus of toughness of the alloys decreased with rise in the zinc in the material.

Abstract: In the present work, comparison of solid particle erosive behaviour of 13/4 steel and Nitrogen alloyed austenitic stainless steel (23/8N steel) have been studied using air jet erosion testing. Air jet erosion testing has been performed at various angles for as received samples at 31 m/s velocity and a discharge rate of 3 gm per minute by alumina particles with angular shape and 53-63μm size. Microstructure, eroded surface characteristics, mechanical properties and erosion rate are characterized by using scanning electron microscope, hardness and tensile testing. 23/8N steel shows good hardness coupled with high tensile toughness and work hardening ability, which leads to improved erosion resistance. The surface morphology analysis of the worn out surfaces, cumulative weight loss measurements and steady state of erosion rate results were used to understand the effect of nitrogen on the degradation mechanisms. The results show that 23/8N steel exhibits excellent resistance to erosion in comparison to13/4 steel.

Abstract: Abstract: Hydroturbine blades in hydroelectric power plants are subjected to erosion. Currently these blades are made of 13/4 martensitic stainless steel (ASTM grade A743). This steel suffers from several maintenance and welding related problems. Nitronic steels are being considered as an alternative to martensitic stainless steels since they have good weldability. In present work, erosive behaviour of 13/4 Martensitic and Nitrogen alloyed austenitic stainless steel (23/8N steel) has been studied. Cavitation erosion tests were carried out in distilled water at 20 KHz frequency at constant amplitude. Microstructure of eroded surface, mechanical properties and erosion rate were characterized. It was observed that 23/8N steel possesses excellent resistance to erosion in comparison to 13/4 martensitic steels. 23/8N steel showed good hardness coupled with high tensile toughness and work hardening ability, leading to improved erosion resistance.

Abstract: Polypropylene/polyamide-6 and polypropylene/metallocene polyethylene blends containing 2.5 phr of organophilic modified montmorillonite were prepared in a twin-screw extruder followed by injection molding. In order to compare, blends without layered clay were also made. Styreneethylene- butylene-styrene copolymer and polypropylene grafted with anhydride maleic were used as compatibilizers in the ternary blends and in the PP nanocomposite preparation, respectively. The presence of tactoids, intercalated and exfoliated structures was observed by TEM in some of the samples containing layered clay and modified PP materials. Results showed that the compatibilized blends prepared without clay are tougher than those prepared with the nanocomposite of PP as the matrix phase and no significant changes in tensile moduli were observed between them. However, the binary blend with a nanocomposite of PP as matrix and metallocene polyethylene exhibited better tensile toughness and lower tensile modulus, than those prepared with a nanocomposite of PP and polyamide-6 as dispersed phase. These results are related to the degree of clay dispersion in the PP and to the type of morphology developed in the different blends. Differential scanning calorimetry (DSC) showed that blends with a finer and homogeneously dispersed morphology determined by SEM, the PA component exhibited fractionated crystallization exotherms in the temperature range of 159-185°C. Also, nucleation of the PP component by PA phase and/or the layered clay was observed in the blends with PA as dispersed phase.