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QUESTION 1 Diffusion (a) The diffusion coefficients for carbon in nickel are given at two temperatures
as shown in Table 1: Table 1 diffusion coefficients for carbon in nickel. T(.C) D(m?/s) 600 5.5 x 10-14 700
3.9 x 10-13 Determine Do and Qa using the diffusing equation: D = D. exp RT where R=8.31 ..

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1000 Austenite, Y Temperature Fe, Cty 800 aty Ferrite, 0- 727C 0.8% 0.02% 600 a + FeC 400 0.00
0.40 0.80 1.20 1.60 2.00 Figure 1: Fe-Fe3C Equilibrium Phase Diagram. Composition of FesC is 6.7% C.
QUESTION 3 Heat Treatments of Steels (a) The TTT curve shown in Figure 2 is for a 1080... 

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800 727 700 Coarse pearlite 600 a + ForC Fine pearlite 400 Bainite 300 200 100 1 sec 1 min 1 hour 1
day 0 0.1 10 10 10 10 105 Time, seconds Figure 2: TTT curve for 1080 steel. (b) Use the Jominy end
quench data in Figure 3 and Figure 4 to answer this question. A bar of diameter 100 mm is ...

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170 150 20 15 07 05 035 020 15 45 Figure 3 Graph relating between Jominy end quench distance and
equivalent bar diameter. AS Db. A9 06 AS416 43 46 HadesHRC O 5 D D 25 35 Figure 4 Relationship
between Jominy end quench distance of a bar and hardness at the centre of the bar for three steels.

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QUESTION 4: Cars mics Processing (a) Explain the types of properties possessed by ceramics which
result in their use in applications in place of metals Give two examples of different ceramics and their
applications to explain your answer. [4 marks] (b) Answer either part (i) OR part {ii} (i) Des...

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Describe possible methods of fabrication of these ceramic structures, including information about a the
methods which could be used to fabricate the parts a the way the ceramic materials are prepared for
the fabrication process a any post?fabrication treatments that need to be used [ti marks] ... 

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Solidification Time, T = c(LY QUESTION 6 Forging (a) List three advantages of impression-die forging
compared to machining from solid stock. (3 marks) (b) What is flow stress and name few material
properties which influence the flow stress (2 marks) (c) What is basic difference between ... 

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(b) What is major difference between Sheet metal forming processes and other bulk deformation
process such as forging and extrusion. (2 Marks) (c) What manufacturing process to be used for
manufacture of tooth paste tube (1 Mark) (d) What is the significance of clearance in sheet...