Mechanical Properties Transformation on Zr54Al17Co29 Bulk Metallic Glass by Partial Crystallization

Study on biomaterials is recently essential for rapid development of medical application and Zr54Al17Co29 BMGbecomes promising candidate due to the lack of toxic elements. Partial crystallization by isothermal annealing at SCL region was used to variate the crystallinities of BMG. The structural and thermal properties of as cast and partially crystallized samples were confirmed by XRD and DSC test, while microvickers and compression test were further utilized to investigate their mechanical properties. By the higher crystallinity, the hardness could be slightly increased in range 540 ± 5 to 575 ± 5 Hv. As-cast sample shows the yield strength and plastic strain of 2130 ± 75 MPa and 2.2 ± 1.6%. The yield strength is increased by the presence of 10% nanocrystal, afterwards, fall and raise phenomena are obtained with further crystallinity. However, with higher crystallinity, the plasticity is significantly degraded and no more plastic strain observed at sample with 50% of crystallinity. Both the presence of nanocrystalline phase and free volume annihilation are the reason of mechanical properties change on the Zr-based BMG

Evaluation of mechanical properties of matrices derived from fish scale collagen

The development of biodegradable materials arises as an alternative to reduce the pollution caused by plastic waste to the environment, with this premise this study was proposed to develop plastic biopolymers from bioactive compounds with different matrices modified cassava starch (5 – 12 %), fish scale collagen (10 – 40 %), lemon essential oil (0,5 - 1,5 %) and gelatinization temperature (70 – 80 °C); A Box Behnken response surface experimental design was used; with the determination of their mechanical properties (maximum stress, Young's modulus, shear strength, stress at break and percentage elongation at break). According to the results found, it was determined that the modified cassava starch had the greatest influence on the mechanical properties, taking into account its importance to create more resistant materials, but it evidences plasticizing difficulties, where the fish scale collagen has a significant influence. In addition, it is evidenced that lemon essential oil had a great influence on Young's modulus (46,28 ± 2,31 MPa) and the percentage of elongation (69,69 ± 2,16 %); while the gelatinization temperature of 80 °C is not recommended for this type of starch-protein matrices due to damage of the structure; determining a better mechanical resistance and a great increase of Young's modulus. In conclusion, the characteristics and performance of the film based on cassava starch, collagen flakes and lemon essential oil have a positive impact on the maximum level of mechanical efficiency of the biodegradable films, achieving a better performance in their mechanical properties.La elaboración de materiales biodegradables surge como alternativa para disminuir la contaminación causada por los desechos plásticos al medio ambiente, con esta premisa, se propuso este estudio comprendido en el desarrollo de biopolímeros plásticos, a partir de compuestos bioactivos con diferentes matrices de almidón modificado de yuca (5 – 12 %), colágeno de escamas de pescado (10 – 40 %), aceite esencial de limón (0,5 - 1,5 %) y temperatura de gelatinización (70 – 80 °C). Se utilizó un diseño experimental de superficie de respuesta Box Behnken; con la determinación de sus propiedades mecánicas (esfuerzo máximo, módulo de Young, fuerza de corte, esfuerzo a la ruptura y porcentaje de elongación de ruptura). Según los resultados encontrados, se determinó que el almidón modificado de yuca fue el de mayor influencia en las propiedades mecánicas, teniendo en cuenta su importancia para crear materiales más resistentes, pero evidencia dificultades plastificantes, donde el colágeno de escamas de pescado incide significativamente. Además, se evidencia que el aceite esencial de limón presentó gran influencia en el módulo de Young (46,28 ± 2,31 MPa), y en el porcentaje de elongación (69,69 ± 2,16 %); mientras que la temperatura de gelatinización de 80 °C no es recomendada para este tipo de matrices almidón - proteína por daños de la estructura; determinando una mejor resistencia mecánica y un gran aumento del módulo de Young. En conclusión, las características y el rendimiento de la película a base de almidón de yuca, colágeno de escamas, y aceite esencial de limón; tienen un impacto al considerar el nivel máximo de eficacia mecánica de películas biodegradables y alcanzar un mejor comportamiento en sus propiedades mecánicas

Investigating of Mechanical Properties of Mortars Based on Fly Ash and Blast Furnace Slag Activated with Alkali

Alkali activated mortars obtained from granulated blast furnace slag and fly ash were used instead of Portland cement by activating with alkali. Sodium silicate and sodium hydroxide were activated blast furnace slag and fly ash. Mortar samples were prepared 40x40x160 mm as prismatic samples according to TS EN 196-1 and they were cured at room temperature. Compressive and flexural strength of the mortar samples including blast furnace slag and fly ash were investigated by experimenting

Thermal conductivity, structure and mechanical properties of konjac glucomannan/starch based aerogel strengthened by wheat straw

This study presents the preparation and property characterization of a konjac glucomannan (KGM)/starch based aerogel as a thermal insulation material. Wheat straw powders (a kind of agricultural waste) and starch are used to enhance aerogel physical properties such as mechanical strength and pore size distribution. Aerogel samples were made using environmentally friendly sol–gel and freeze drying methods. Results show that starch addition could strengthen the mechanical strength of aerogel significantly, and wheat straw addition could decrease aerogel pore size due to its special micron-cavity structure, with appropriate gelatin addition as the stabilizer. The aerogel formula was optimized to achieve lowest thermal conductivity and good thermal stability. Within the experimental range, aerogel with the optimized formula had a thermal conductivity 0.04641 Wm−1 K−1, a compression modulus 67.5 kPa and an elasticity 0.27. The results demonstrate the high potential of KGM/starch based aerogels enhanced with wheat straw for application in thermal insulation

Study Of Mechanical Properties Of Aluminium Lm25 Using Stir Casting Method

The present study deals with the behaviour of aluminium hybrid alloy based composites, reinforced with fly ashnbsp particles and solid lubricants such as activated carbon .The first one of the composites consists of Al. with fly ash particlesnbsp and activated carbon. The other composite has Al with fly ash and solid lubricant: activated carbon at solid state. Both composites are fabricated through lsquoStir Casting Methodrsquo. Mechanical properties of the samples are measured by usual methods such as Hardness,Tensile .The tested samples are examined using Scanning Electron microscope (SEM) for the characterization of microstructure on the surface of composites. The Main Aim is to be results of the proposed Hybrid composites are compared with Al based metal matrix composites at corresponding values of test parameters

Predicting Mechanical Properties of Galvanized Steels: Data Mining Approach

The purpose of this paper is to predict the mechanical properties of galvanized steel, using appropriate data mining techniques such as neural network, support vector machine, regression analysis and regression tree methods. It is found that by using the neural network technique one can get the best result for predicting the mechanical properties of galvanized steel according to the values of input parameters and also considering the effects of annealing temperature and line speed as the controlling parameters

Synthesis and Mechanical Properties of Polyurethane-modified Epoxy Based on Glycerol Monooleate Ester

Polyurethane-Modified Epoxy (PME) is one of methods in epoxy modification to address some epoxy drawbacks, especially on tensile strength. In this research, epoxy modification using polyurethane has been performed by adding glycerol monooleate ester as polyol. Synthesis of glycerol monooleate ester (GMO) is done via an esterification reaction glycerol with oleic acid with sulfuric acid as catalyst with a yield of 80%. Synthesis of PME based on Ester Glycerol Mono-Oleate (PMEGMO) is performed by reacting epoxy, tolonat and GMOs at 50°C for 30 minutes and produce a yield of 80% Characterization of functional groups and structure of the synthesized GMO and PMEGMO are done by using FTIR and NMR. PMEGMO films is made by adding hardener. Analysis results of the mechanical properties show that the synthesized PMEGMO has two-fold higher tensile strength compared to unmodified epoxy caused by the presence of polyurethane

Physical and Mechanical Properties of Three Polystyrene Impregnated Indonesian Wood Species

The disadvantage of fast-growing species is that they have inferior physical and mechanical properties. Polystyrene impregnation can be applied to improve physical and mechanical properties. Wood samples, which were dried until 10% moisture content were put into impregnating tank and vacuum pressured at 20-mm Hg for two hours. During the gradual release of vacuum, styrene monomers, vinyl acetate monomers and terburyl-peroxide catalyst was streamed into the tank. Afterwards, the pressure inside the tank was allowed to decrease to 500 mm Hg and kept for 60 minutes. Wood samples which had been impregnated were subsequently immersed in water, then wrapped in aluminum foils and put in the oven for 24 hours at 60°C. The samples were then tested for the polymer loading and their physical and mechanical properties. The results showed that the polymer loadings in wood plastics with the species of origin (i.e. consecutively sengon, pine and rubber wood) were 118%, 72% and 44%, respectively. Impregnation with polystyrene (copolymer of styrene and vinyl acetate monomers) could improve the physical and mechanical properties of wood plastics, i.e. specific gravity, moisture content, water absorption, shrinkage/ swelling, compression parallelto the wood grain, MOR and MOE. Greater use of vinyl acetate decreased physical and mechanical properties