UNIVERSITY OF SOUTH AUSTRALIA ENGINEERING MATERIALS TECHNICAL WRITING REPORT XXXXXXXXXXPage 1 Brief The aim of this activity is to solve simple engineering and material selection problems, and to...

Technical writing report. Engineering materials classattached document


UNIVERSITY OF SOUTH AUSTRALIA ENGINEERING MATERIALS TECHNICAL WRITING REPORT Page 1 Brief The aim of this activity is to solve simple engineering and material selection problems, and to develop writing and communication skills. A high performance racing catamaran is being designed. The total width of the catamaran is 7m, and the maximum compression load on the mast is expected to be 1000kg. Maximum deflection of the beam should not exceed 50mm. The load on the 15m wire stays is expected to be a maximum of 600kg each. The mass of the hulls and mast together is 500kg (not including the beam and stays). The catamaran will be lifted out of the water each day by a crane using a single lifting point. The lifting wire must be strong enough to lift the combined weight of the hulls, mast, beam and stays. You must: 1. Specify the material to be used for the beam and calculate the diameter. Assume the beam is cylindrical with 1000kg load applied in the middle. 2. Specify the material to be used for the wire stays and calculate the diameter. 3. Specify the material and diameter to be used for a wire to lift the catamaran out of the water. Choose appropriate safety factors for each. Figure 1. Diagram of components to be designed. ENGINEERING MATERIALS TECHNICAL WRITING REPORT Page 2 Remember: 1. Your report should contain the following sections: Title and authors Executive Summary (approx. 100 words) Discussion (approx. 200-250 words for each design element) Conclusions (approx. 100 words) References (approx. 6-10) Appendix (include all calculations/tables etc for each element) 2. You should discuss why you choose certain materials and sizes for the application instead of the alternatives listed below in Table 1. ENGINEERING MATERIALS TECHNICAL WRITING REPORT Page 3 Table 1. Properties of materials to be selected from. Some useful equations for bending (also see Ch 12 in textbook) Stress for a rectangular section beam ??? = 3??? 2??2 Stress for a circular section beam ??? = ??? ? ?3 Deflection for a rectangular section beam ∆? = ??3 4 ? ? ?3 Deflection for a circular section beam ∆? = ??3 12 ? ??4 Material Yield Stress (MPa) Tensile (or Compressive) Stress (MPa) Elastic (or Flexural) Modulus (GPa) Density (kg/m3) Steel 200 307 200 7890 Aluminium 70 110 70 2700 Copper 150 180 110 8960 Titanium alloy 880 950 110 4510 Silicon Nitride 820 830 310 3440 Oak 40 70 11.3 780 Fibreglass 235 250 24 1900 Prepreg Carbon fibre 1800 1860 150 1600 Concrete 3 3 4.5 2200 Glass 70 75 80 2200 Reinforced Polycarbonate 85 90 23 1200 ENGINEERING MATERIALS TECHNICAL WRITING REPORT Page 4 Marking Scheme Assessable element Comments Marks Word count Not including Title, author and references Marks deducted if outside the recommended range. /2 Sections The report should be suitably formatted and address all section headings Title and author Executive Summary Discussion Conclusions References Appendix /3 Technical content The report should demonstrate knowledge of the properties and use of materials with relevance to the chosen topic. Materials selection criteria should be addressed in detail. The quality of the referencing will also be assessed. Possible examples of relevant properties include stiffness, toughness, durability, density, strength-weight ratio, cost, ease of manufacture etc /12 Appendix Calculations to be accurate, suitably presented and answers valid /3 Total /20