ABSTRACT
A tensile test is performed on a sample of 1045 normalized construction-grade steel using an Intron load frame. A graph of the engineering stress versus strain of the 1045 steel specimen is constructed from the data collected in the tensile test. Mechanical properties such as the ultimate strength, the fracture strength, and the Young’s modulus of the sample are obtained by further analyzing the stress versus strain graph. These experimental values are compared to the expected mechanical properties of the tested material provided by a reference. The percent difference between the expected and experimental values of the ultimate strength is 13.5% and that of the modulus of elasticity is 9.42 %. INTRODUCTION Background
In many engineering
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The diameter of the grip section is then measured and recorded after the gage diameter is acquired. The specimen is then loaded onto the testing machine and the upper grip of the load frame is tightened by turning the handle above the upper grip. The jog button is used to lower the crosshead to center the specimen between the two grips[2]. Once the specimen is aligned, the lower grip is tightened up by turning the lower handle. The crosshead position is then initialized by using the control panel and the extension display is set to be zero. Next, an extensometer is attached firmly to the gage section of the specimen to measure the change in length. The strain indicator in the computer program is ascertained to be close to zero. After calibrating and double-checking the set-up, the tension test begins and the computer program starts to collect the data when the “Start” button is …show more content…
Compared to the expected value, the ultimate strength obtained from the experiment, 647 MPa, is greater than the anticipated value. The percent difference between the expected and experimental values is 13.5%. There is also a discrepancy between the expected and experimental values of modulus of elasticity of 1045 steel. The expected value of modulus of elasticity is 200 GPa[3] while the experimental value is 182 GPa, which is slightly smaller than expected. The percent difference calculated is 9.42 %.
One of the possible sources of error is the sample size. The expected mechanical properties are obtained based on multiple repetitive experiments on 1045 steel specimens of different dimensions, whereas only one sample is tested in this experiment. By increasing the sample size, the experimental values might be closer to the theoretical mechanical properties. In addition, failure to calibrate or check zero of the equipment used could affect the accuracy of the instrument, and therefore could result in the discrepancies between the expected and experimental values.
We use metals to construct all kinds of structures, from bridges to skyscrapers to elevators. The strength as well as durability of materials that are crafted out of metal make the materials ideal not only for construction but also for many other applications.
Elastic strain region at small and big end of connecting rod is shown in figure no. 10. The maximum and minimum equivalent strain values are 0.00033975 and 2.1407e-10 respectively. Due to applied pressure there will be change in original dimensions of the connecting rod and hence strain developed can be
Two elastic bands were placed on the tube 60 cm (600 mm) apart measured to the nearest 0.1 cm. The first band placed low enough so that the ...
In the experiment these materials were used in the following ways. A piece of Veneer wood was used as the surface to pull the object over. Placed on top of this was a rectangular wood block weighing 0.148-kg (1.45 N/ 9.80 m/s/s). A string was attached to the wood block and then a loop was made at the end of the string so a Newton scale could be attached to determine the force. The block was placed on the Veneer and drug for about 0.6 m at a constant speed to determine the force needed to pull the block at a constant speed. The force was read off of the Newton scale, this was difficult because the scale was in motion pulling the object. To increase the mass weights were placed on the top of the ...
The structural torsional stiffness is calculated through finding the torque applied to the handle and dividing it by the angular deflection of the handle that is resulted from the torsional loading. It is expressed in term of Nm/degree of angular deflection. This calculation is shown below in figure 3.1
...tem Solutions) laboratories, Peenya Industrial area, Bangalore. During preprocessing, stress vs. strain curves (obtained from the tensile tests) are entered while defining standard piecewise linear rate dependent plasticity material models. The material properties of Aluminium alloy (Al6063-T6), SMC (Sheet Moulding Compound) and GMT (Glass Material Thermoplastic) are extracted from different journal papers during literature review. These material properties are required to be entered in Kinematic Hardening material model during the preprocessing stage. On the other hand, experimental rate of work decay is evaluated as area under force vs. displacement curve (obtained from three point bending tests). Experimental contributions made by few researchers in the field of high velocity impact crashes facilitated the specific energy absorption values for different materials
Laws such as the lever law and Euler’s Buckling Theorem come into play when testing and competition begins. A structure of wood and glue surely has much more to offer than meets the eye.
For 4.1, the lab was to slide a certain amount of blocks of a different surface for four trials for each surface. There was a spring scale attached to a block and then, the directions were to pull it
Mechanical Engineering 130.2 (2008): 6 - 7. Academic Search Complete. Web. The Web. The Web.
Comparing the joints welded with two different heat inputs, concluded that the ultimate tensile strength (UTS) and impact toughness of the welded joints decreases with increases the heat input.
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A crystalline material can be either a single crystal or polycrystalline. Material with Polycrystalline consists of many crystals separated by well-defined boundaries whereas a single crystal consists of only one crystal. It is difficult to prepare single crystals when compared to polycrystalline materials, and more effort is needed for the growth of single crystals. There are two main reasons for the intended growth of single crystals. Many physical properties of solids are complicated by the effects of grain boundaries. The full range of tensor relationships between an applied physical cause and an observed effect can be obtained only if the total internal symmetry of the crystal structure is continued throughout the
Metals possess many unique fundamental properties that make them an ideal material for use in a diverse range of applications. Many common place things know today are made from metals; bridges, utensils, vehicles of all modes of transport, contain some form of metal or metallic compound. Properties such as high tensile strength, high fracture toughness, malleability and availability are just some of the many advantages associated with metals. Metals, accompanied by their many compounds and alloys, similar properties, high and low corrosion levels, and affects, whether negative or positive, are a grand force to be reckoned with.
I have spent so much time learning about design through the paradigm of materials but now I want to connect mechanical aspects to the knowledge I have already gained. I am particularly interested in the research done by Dr. Drew Nelson, Dr. Sheri Sheppard and Dr. Friedrich Prinz whose work most closely fits my interests. I am interested in doing research in mechanical design as influenced by material usage. I am also looking forward to taking courses such as Imperfections in Crystalline Solids, The Magic of Materials and Manufacturing, and Nanomaterials Synthesis and Applications for Mechanical Engineers to explore topics I have already studied, but from a mechanical engineering perspective. Stanford’s combination of rigor and creativity appeal to me. I have always enjoyed a challenge and get great satisfaction from expanding my knowledge. Coming from a Materials Science and Engineering background where I have performed well, both in academics and leadership, I know I can be an asset to and learn from the world-class Mechanical Engineering program at
Experimental Mechanics involves the experimental investigations of the static and dynamic response of structures and machines, and in the development of improved techniques to obtain and analyze experimental data.