As weight-saving assumes greater importance in automobile design, the replacement of steel parts with polymer-composite substitutes becomes increasingly attractive. Weight can be saved by replacing a steel hood with one made from a thermosetting composites. The weight of the hood depends on the car model: a typical composite hood weighs is \(8-10 \mathrm{~kg}\). The shape is a dished-sheet and the requirements on tolerance and roughness are \(1 \mathrm{~mm}\) and \(2 \mu \mathrm{m}\), respectively. A production run of 100,000 is envisaged.

a. List the function and constraints, leave the objective blank and enter 'Choice of process' for the free variable.

b. Use the charts of Figs. 7.3, 7.4 and 7.6 to identify processes to shape the casing.

Data From Fig. 7.3

Data From Fig. 7.3

Data From Fig 7.6

Transcribed Image Text:

Metals, ferrous Metals, nonferrous Ceramics Glasses Elastomers Thermoplastics Thermosets Polymer foams Composites 0000 0 0 Shaping Sand casting Die casting Investment casting Centrifugal casting Forging Extrusion Sheet forming Powder methods Electro-machining Machining Injection moulding Blow moulding Compression moulding Rotational moulding Thermo-forming Polymer casting Resin-transfer moulding Filament winding Lay-up methods Vacuum bag Additive manufacture 0