Vibration Test of Composite Materials on the Basis of Measurement of Dynamic Properties

Experimental stress analysis is a method of stress and strain testing of materials, to test for behaviour changes of materials under fatigue. The first method of stress analysis used was the Strain Gauge invented by Edward E. Simmons and Arthur C. Ruge created in the late 1930s to test for earthquake stress on elevated water tanks[1]. The creation of lasers and interferometry methods in the 1960s provided the basics of digital image correlation where high-speed cameras could be used to capture behaviour changes in materials during deformation. As the years went on, advancements in imaging, laser and sound technology allowed for new innovative techniques to be used to measure strain and stress. Some of these techniques include are digitised ultrasound images, non-linear least squares and robust stereo-vision system[2].

Some of the challenges in analyzing tool marks is it is difficult to duplicate the marks left by tools through tests in the laboratory and tool marks may not always give individual characteristics.

The tensile testing was done on the three composite specimens (90°, and two 45°) were completed with a servo-hydraulic load frame with a wedge. The one in the lab was the MTS 647 hydraulic wedge grip and an 810 material test system. The specimens had strain gages with a Wheatstone bridge to collect data such as time, distance, load, axial strain, and transverse strain. From the strain gages, evidence can support how and when the specimen material failed under the stress being applied to it. The test was run for three times on three different specimens. The first specimen that was tested in the hydraulic load was the 0°/90° specimen, which is made of carbon and epoxy laminate composite.

However, the absence of plastic deformation does not mean that composites are brittle materials like monolithic ceramics. The heterogeneous nature of composites result in complex failure mechanisms which impart toughness. Fiber-reinforced materials have been found to produce durable, reliable structural components in countless applications. The unique characteristic of composite materials, especially anisotropy, require the use of special design

Some of the challenges in analyzing tool marks is it is difficult to duplicate the mark left by tools through tests in the laboratory and tool marks may not always give individual characteristics.

Jaglinski, T., et al. “Composite Materials with Viscoelastic Stiffness Greater than Diamond.” Science, vol. 315, no. 5812, 2007, pp. 620–622., www.jstor.org/stable/20038881.

used in the manufacture of products such as paint and children toys. Corrective measures can

This report aims to describe the experiment performed to investigate the stiffness of a channel section, and in particular calculate the flexural rigidity (EI) of the beam by two different sets of calculations based on the results gained in the experiment. The EI of an object is used

In laboratories regular maintenance of the analyzers, proper measurement of samples and accuracy in method may avoid these.

Engineering involves a wide array of problems that must be overcome. A great deal of time is spent researching materials and their properties. Materials compromise all aspects of our society, from buildings to roads to even the equipment that was used in this lab. Problems arise in regards to how strong or flexible the material is, with the official terms being stress, strain, and elasticity. Improper use of such materials results in tragedies such as the Tacoma Narrows Bridge in Washington that failed to due resonance and stress beyond its elastic limit [1].

Modulus of elasticity also known as Young’s Modulus measures the stiffness or firmness of a material. When choosing a polymer for soft tissue replacement, we should choose a material that has a middle range modulus of elasticity. The Modulus of elasticity should not be too high because it would cause lack of mobility. On the other hand, the Modulus of elasticity can't be too low because then the soft tissue will not be able to support weight. Choosing a polymer with a middle range Modulus of elasticity allows for both mobility and

The speech of George W. Bush can be considered a highly effective speech because it set the foundation of the policy of the US since 2000 to present and perhaps next 15-20 years. The speech started with:

Elasticity is a bill of responsiveness. The responsiveness of measured by variable quantity Z to a modification in

A composite material is a material that is made of (composed of) 2 or more constituent materials with different physical and chemical properties of each other. When combined, these materials form a composite with different properties from both of its constituent. Composite material is preferred for many reasons. It is often stronger, lighter, and less expensive when compared to traditional materials. Engineered composite materials, for example, are: mortars, concrete, metal composites, reinforced plastics, and ceramic composites. Nowadays, composites are widely used in many fields, especially in industries. Industries including oil and gas industry now use composites as their equipment’s material. One of the strongest reason why composites are now widely used, is that, use of composites lower the production cost for

Purpose: The purpose of this Physics Lab is to investigate what factors determine the amount of flexion of the cantilever. Hence, the objective is to establish a relationship between the length of a cantilever, which may give some insight into the physics of cantilevers.