Question

9. Use of the four segment chart for strength. Use the 4-segment chart for strength- mass per unit length, m/L of a section with Zơ,-10 Nm (where Zis the section modulus) made from (a) 6061 grade aluminum alloy with a shape factor of 3, strength σ ,-200 MPa and density ρ (b) a titanium alloy with a shape factor of 10, , strength ơ ,-480 MPa and density . 4420kg/m limited design to compare t -2700 kg/m", and 10. Selecting shaping processes. A process is sought to make the rocker arm shown here. It is to be made from an aluminium-silicon alloy. The shape is "3-D solid". The expected production run (batch size) is 2,000. It wei 1kg. Surface roughness and tolerance are not critical because the bores and the boss will be machined to final size. Comment on each of the following processes with regards to the process compatibility with shape, process compatibility with batch size, and product quality. Sand casting Die casting Investment casting Centrifugal casting Forging Extrusion Sheet forming Powder methods Electro-machining Machining from solid Additive manufacture

problem 10

Answer 1

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