Comparison of the mechanical properties of flax and glass fiber composite materials

In this paper, the comparison of static and dynamic properties of flax and glass fiber composite materials is presented. For this comparison, dynamic and quasi-static experimental studies were carried out. As a dynamic test, vibration tests were fulfilled using the Oberst apparatus and the tensile test was fulfilled by a quasi-static test. The vibration tests were carried out under different temperatures by using temperature and climatic test cabinets. Flax and glass fibers were used as reinforcements, and polyester resin was used as a matrix to make up the composite specimens. According to the obtained results, the strength of flax fiber composite is lower than the glass fiber under tensile loading, but approximately the same under vibration excitation. On the other hand, damping characteristics of flax fiber composite is higher than glass fiber composite materials. These results demonstrated that natural fiber materials can be used instead of chemical materials for vibration absorption due to their high damping

Influence of pretension on mechanical properties of carbon fiber in the filament winding process

The present study has investigated the effect of the roving tension (pretension force) on the strength of continuous carbon fiber used in the Filament Winding (FW) process. Pretension force is generally applied to composite products manufactured by FW technology to lay out the carbon fiber onto the cylindrical tube in a correct way. However, a considerable amount of damage occurs in the fibers during fiber movement trough pulleys in the pretension unit. A winding system was designed to simulate the process to understand the effects of the parameters such as roving tension, pulley diameter, and contact angle between pulley and fiber. Several experimental tests have been performed by changing pulley diameters and tension forces to understand the effect of these parameters. According to these experiments, the angle between the pulley and the amount of force applied to the carbon fiber generate the damage on the carbon fiber. Tension tests were also conducted to evaluate the strength of the damaged and undamaged carbon fiber. Experimental results indicate that the tensile strength of carbon fiber is reduced by 10 to 43% because of a change to the roving tension (pretensioning) parameters

Caliper simulation using computer for vocational and technical education

In this study a caliper simulation was developed as computer application for using in the Vocational Education and Training (VET) and Distance-based training. This simulation was developed for teaching the caliper as measurement tool based Metric and Whitworth measurement systems. The developed caliper simulation introduced in detail step by step as user guide. The vernier scales are simulated as 1/10, 1/20 and 1/50 for metric measurement system and 1/64, 1/128 and 1/1000 for Whitworth measurement system. This simulation can easily be download and setup as computer software. To the best of the authors’ knowledge, this is the most important application for students to study everywhere they would like

Caliper simulation using computer for vocational and technical education

In this study a caliper simulation was developed as computer application for using in the Vocational Education and Training (VET) and Distance-based training. This simulation was developed for teaching the caliper as measurement tool based Metric and Whitworth measurement systems. The developed caliper simulation introduced in detail step by step as user guide. The vernier scales are simulated as 1/10, 1/20 and 1/50 for metric measurement system and 1/64, 1/128 and 1/1000 for Whitworth measurement system. This simulation can easily be download and setup as computer software. To the best of the authors’ knowledge, this is the most important application for students to study everywhere they would like

Investigation of the Acoustic and Mechanical Properties of Homogenous and Hybrid Jute and Luffa Bio Composites

Design and development of new biomaterials has become a necessity due to adverse effects of chemical materials on people and nature. As the mechanical properties of biomaterials are not as good as those of chemical materials, their different configurations should be developed and tested before considering them for practical applications. Acoustic and mechanical properties of homogenous and hybrid jute and luffa biocomposites are investigated here. Homogenous and hybrid composites using jute and luffa fibers and epoxy are designed and manufactured and methods for identification of the acoustic and mechanical properties are summarized. Acoustic and structural frequency response functions are measured using homogenous and hybrid composite plates to determine their natural frequencies and loss factors. Using the experimental modal parameters of the plates and their theoretical models, elasticity moduli of biomaterials are determined. The acoustic absorption properties and transmission losses of homogeneous and hybrid composites are determined using impedance tube method. Results show that homogenous and hybrid jute and luffa composites can have moderate absorption coefficients (0.1 for a thickness of 4 mm) and superior damping performance of luffa and stiffness property of jute can be used together to produce hybrid composites with high damping (2.2–2.6%) and elasticity modulus (3–5 GPa)