• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

To select a material using a computer database called 'Cambridge Engineering Selector' (C.E.S).

Extracts from this document...


Object To select a material using a computer database called 'Cambridge Engineering Selector' (C.E.S) Apparatus - Computer - 'Cambridge Engineering Selector' database program Theory The Problem Below is a brief description of the theory regarding this lab: - Oars are light, stiff beams. They must also have reasonable fracture toughness (KIC) and acceptable price per unit mass (Cm). The performance index for a light, stiff beam is: M1 = E1/2/? Where E is the Young's modulus and ? is the density. To select the best materials, perform two selection stages: (i) In stage 1, select materials with M1 > 7 (GPa) /(Mg/m) (ii) In stage 2, select materials with KIC > 1 MPa.m and Cm < 100 GBP/kg. CES Selector Materials for Oars: The solution The performance index for a light, stiff beam (M1) is plotted in stage 1. 'Density' is plotted on the x-axis and 'Young's Modulus' on the y-axis. A selection line of gradient 2, through the point (1.0, 49) is plotted. The constraints on adequate fracture toughness and price are plotted in stage 2. 'Fracture Toughness' is plotted on the x axis and 'Density' on the y axis. A selection box whose upper left corner is at (1.0, 100) is defined. In stage 1, the line representing the performance index is moved 'up' until only a small subset of records remains in the selection. Magnified views of the two selection charts are shown in figures M5.3.1 and M5.3.2 (results intersection and hide failed records on), and the materials passing both stages are shown in figure M5.3.3. ...read more.


CALCULATION OF THE GRADIENT FOR BOTH GRAPHS The gradient of the lines in both graphs were calculated using the performance index for the bending of rods, the formula used was: - E/P = Young's Modulus / Density In order to get the above equation into the correct term for a gradient or a curve (y=m x + c) both sides of the equation had to be logged: LOG E - LOG ? = LOG C Transpose for LOG E LOG E = LOG ? + LOG C The equation for a straight line is y = mx + c From the above it is fair to mention that: - Y = LOG E X = LOG ? M = 1 The performance used in this lab was E 1/2 / P = C If you take log on both sides of the equation above: 1/2 LOG E - LOG ? = LOG C Transpose for 1/2 LOG E: LOG C + LOG ? = 1/2 LOG E Multiply both sides by 2 to get LOG E LOG E = 2 LOG ? + 2 LOG C From the above it can be assumed that: Y = LOG E M = 2 X = LOG ? C = 2 LOG C M (The gradient) = 2 The gradient in the first graph of Density Vs. Young's Modulus is 2. If another performance index is used: K IC / p = c The log of both sides of the equation gives: - 2/3 LOG K ic = LOG ? ...read more.


). But in the economical end of manufacturing rowing boat oars, both the wood materials would be selected, as they are reasonably cheap to buy, whereas carbon fibre is more expensive. Costs of materials are not the only concern, as the usage of each material is just as important. Questions could be asked; such as, how often is the boat going to be used? Is it going to be used on a regular basis? All of these questions should be taken into consideration before a decision is made. If an average person who is not a professional rower was going to consume a rowing boat ore, he/she would be better off opting for the one made from low density wood as the wooden ore is a great deal cheaper. On the other hand if the same question was asked to a professional rower, then the rower would pick the ore made of carbon fibre since the price does not come at the top of the list of concern and winning the race is the major objective. Basically, there is a good point and a bad point on each material. This largely depends on the object of buying the ore. If it is to win a race then money is not an option and the consumer would be better off buying the one made from carbon fibre but if the object is to just go rowing for a weekend then the best option would be to go for the oar made from wood simply because there is no likely consistent further use for the ore. YHAREES KHAN BSc Mechanical Engineering ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Resistant Materials section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Resistant Materials essays

  1. The task has been set to make a hole punch (used to punch holes ...

    blue, rule, scriber, hacksaw Don't spill marking blue 10 12 10 Cut external thread of 20mm Cutting paste, M4 die and die-stock Secure punch in vice when cutting thread 8 10 11 Create rake angle on opposite end Triangular file Secure punch in vice when filing 4 3 12 Screw


    The easiest way to distinguish Nylon from other plastics is to place a small piece in a Pyrex tube and heat the end of the tube gently with a small flame until the polymer has melted partially and undergone some decomposition.

  1. My aim of this experiment is to recognize which material is the greatest sound ...

    However, I found that increasing the number of layers would make this experiment more interesting. I was also going to investigate different thickness of insulation; however I was unable to carry this further as I was unable to get hold of the different material thicknesses.

  2. A new branch of a major Chinese take away, Wok In, is opening in ...

    I also found that fast food take and take away restaurants have very different needs in terms of packaging. Many fast food restaurants do not use crockery, but instead serve the food in plastic and card containers. Paper and card are used extensively in the packaging industry, as they are

  1. Stretching Materials

    both have an increase in extension due to the molecular structure of the material. However, there is not direct relationship as there is no link between the two factors. Evaluating My Evidence Looking back on the experiment I have carried out successful, dependable procedure that has given me precise and reliable evidence.

  2. Metallography. The objective of our experiment is to learn specimen preparation techniques in metallography ...

    The three most widely used resins include bakelite, diallyl phthalate, and melamine. Thermoplastic resins also require heat and pressure during molding, but must be cooled to ambient temperature under pressure. Grinding is a method of surface preparation that involves the use of an array of sanding material of increasing fineness, most commonly sandpaper, to prepare the surface for examination.

  1. ORMOCER&amp;amp;reg;s - A new class of polymeric material.

    Glass fibres based on silica, for example, can be dispersed within an organic polymer matrix to provide structural reinforcement. Such materials are known as composites or class I hybrids, and display some degree of combination of the physical characteristics of their components.

  2. The Progression of the Sail Boat from Past to Present and beyond

    The engineers needed to allow the boat to sail closer to the wind on a narrower angle of attack. The first successful designs appeared on the Red Sea called the 'Arab Dhows'. Another design included the 'Bristol Channel Cutters' around England that also proved itself as an effective windward sailing vessel.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work