Materials

(Abiola). Before the tests, samples are cut into piece from the core with thickness about 1 in, and polished to make the top and bottom surfaces parallel. All tests are proceed on Nanovea Indenter perpendicular to the bedding direction. As natural material, the shale rock samples are not homogenous, so for each sample, at least 12 tests are done on the sample and averaged to get a result to be statistically correct. The indentation points are chosen carefully using the microscope before each…

In this model the ignition time of a particle in the explosive was equal to its distance to the ignition point divided by the detonation velocity. The *MAT_NULL material and *EOS_LINEAR_POLYNOMIAL equation of state in LS-DYNA were used to express the above constitutive relations. The interface of Euler and Lagrange elements at the detonation model were coupled using Arbitrary Lagrangian-Eulerian (ALE) method [36…

Lucian poet Derek Walcott, “The discontent that lies in the human condition is not satisfied simply by material things.” Throughout history it has been proven time and time again, that those who rely on material objects such as money, stature, and fortune, often find themselves in a place of dissatisfaction, and envy. These negative feelings occur for no good reason other than the fact that “material things” are just “things”, and have no real meaning or purpose. Concepts like meaningful…

Determination of the gel-point of a resin via DMA testing and its use in a practical sense The DMA is used to determine the modulus values of the resin to associated temperatures and frequencies. The state of viscosity of the resin is also monitored through the evaluation of tan delta values. Gel-point of a resin implies that resin matrix has transformed into an elastic gel state and can no longer flow. The viscosity shows a sudden rise to extremely high values. The time at which this state is…

Based upon OSHA’s Best Practices for Hospital-Based First Receivers(OSHA 3249-08N 2006) and ATSDR’s Managing Hazardous Materials Incidents(HSEES 2001), PPE recommended for hospital first receivers is Level C+ (Level C with additional respiratory protection), and consists of; 1) A powered air-purifying respirator (PAPR) with chemical cartridges, 2) A chemically resistant suit, 3) Double gloves, and, 4) Chemically resistant boots.…

Linear Horn: The linear horn, also known as the straight-sided horn, is a cone-shaped shell with no curvature, it is the oldest and simplest design. The pressure change through the horn is linear as a sound wave moves through it, so there is no distortion of the sound. The gradual change in the cross-sectional area of the horn decreases distortion and provides a good phase response due to compressed air in the throat. Devices intended to reproduce human voices, such as the megaphone, are…

Moulding has more waste than when compared to other processes. To achieve the desired finish with Compression Moulding, the mould cavity is overfilled to some degree, in order to achieve the correct pressure to form the part correctly. Sometimes, excess material is used to push unwanted air out of the cavity, in order to have a void-free part. Another downside to this method, is that Compression Moulding does require a lot more manpower than some other methods being used. Therefore, there is a…

chemistry, Mathematics, Thermodynamics, Heat Transfer, Material science etc., Tribological problem leads to the reason of metal failures than the mechanical problem such as fracture, fatigue and plastic deformation. 1.6.1 Friction Friction is the opposes that the motion (either sliding or rolling) of the object. This oppose force acts against to its motion is called friction force as shown in fig.1.7. The friction is not a property of material, but it is a system response. The ratio of…

Copper is a nonrenewable material. It comes from a mineral deposit that the time it takes to produce copper is too long to be concidered renewable. According to the Copper Alliance, copper is 100% recyclable. In fact, 9 million tones of copper is recycled each year. The recyclable process of copper uses 85% less energy than its original production. When a person is exposed to uncoated copper such as in coocking pans or drinking utenciles, copper can be toxic. Copper is a durable, tough…

During my graduate studies, I plan on studying aerospace engineering, with an emphasis of materials. Specifically, how materials behave and endure in extreme conditions like high radiation, high and low temperatures, and long durations of vacuum exposure. Once I graduate with my PhD in Aerospace Engineering, I will continue to conduct research and teach students…