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
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
e 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
eam 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
XXXXXXXXXXPage
2
Remember:
1. Your report should contain the following sections:
Title and authors
Executive Summary (approx. 100 words)
Discussion (approx XXXXXXXXXXwords 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
XXXXXXXXXXPage
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 XXXXXXXXXX
Aluminium XXXXXXXXXX
Copper XXXXXXXXXX
Titanium alloy XXXXXXXXXX
Silicon Nitride XXXXXXXXXX
Oak XXXXXXXXXX
Fi
eglass XXXXXXXXXX
Prepreg Ca
on
fi
e XXXXXXXXXX
Concrete XXXXXXXXXX
Glass XXXXXXXXXX
Reinforced
Polyca
onate XXXXXXXXXX
ENGINEERING MATERIALS TECHNICAL WRITING REPORT
XXXXXXXXXXPage
4
Marking Scheme
Assessable element Comments Marks
Word count Not including Title, author and
eferences
Marks deducted if outside the
ecommended 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