Metallic
Question one
Design of a processing route to achieve a microstructure that has very fine second phase aluminum alloy 2024
In obtaining fine precipitates for phase two (Ɵ), the alloy is heated to a maximum Cu wt% = 5.65, which comprises a dual-phase (Al+Ɵ ), which is above the solvus level. Single-phase (Al ) is formed above the solvus line (Xie et al. 140). The alloy is then quenched rapidly to very low temperatures, which results in the formation of single-phase supersaturated (Al). Fine precipitates of the second phase are then formed through allowing aging at a much lower temperature.
The above process is possible for alloys that have a max. wt% Cu = 5.65 approx.
For equilibrium cooling, where the transformational temperature is very high, and this is, therefore, accompanied by much slower nucleation, and the much faster growth results in the formation of course precipitation. For the quenching processes and then ageing, the associated temperature for transformation is also very low, and these, therefore, results in a much faster nucleation process. The slow growth results in precipitates which are fine and equally distributed during the second phase of the process.
Question two
The initial rod diameter is 8mm.
The yield strength was obtained at 250mpa.
For the circular cross-section, the final diameter was obtained as 3mm, and the intended percentage ductility need to stand at 15%.
The yield strength intended for the design needs to stand at least 25% EL.
The ductility also need not exceed the 29.7% EL
The difference is then split, and 28% is then chosen for the design work. The annealing process can be commenced, but the more cold process is also essential and must, therefore, be done (Xie et al. 145). The annealing process is done and to the cold work done until the 28% requirement.
100
72
This implies that a diameter of 12.5mm is needed before the commencement of the last cold work
35=.100, consequently cold work =100
So the zero cold work is chosen at 12.3mm.
This accounts for approximately 60% of the entire cold work process.
The final results and solution.
Cold work=59.7, which is approximately 60% of the entire cold work process.
Work Cited
Xie, Z. M., et al. “Achieving high strength/ductility in bulk W-Zr-Y2O3 alloy plate with hybrid microstructure.” Materials & Design 107 (2016): 144-152.