Synthesis and Properties of Elevated Temperature P/M Aluminum Alloys
Author | : Morris E. Fine |
Publisher | : |
Total Pages | : 34 |
Release | : 1982 |
ISBN-10 | : OCLC:227559226 |
ISBN-13 | : |
Rating | : 4/5 (26 Downloads) |
Book excerpt: In dispersion strengthened high temperature alloys the particle radius is theoretically predicted to be proportional to (Sigma DC sub 0 1/3 where sigma is the interfacial energy, D, the diffusivity, C sub 0 the solubility limit and t is time. Thus, information about sigma, D, and C sub 0 are needed to design and evaluate high temperature alloys. The A1-8Fe-3Ce alloy developed by Alcoa Research center is being studied on this basis. Assuming diffusion of iron is rate controlling, values of sigma are calculated indicating an incoherent interface; however, the coarsening is more complex than predicted by the simple theory. Low values of sigma are expected when there is good lattice matching across the interface. A13(Ti, Zr, Hf) is being studied seeking good lattice matching. A13, (Ti, Zr), A13(Ti, Hf), A13(Zr, Hf) have been studied to date and the best matching is obtained with A13(Ti0.75 Zr0.25) where the lattice mismatch between the compound and aluminum is 3-4%. (Author).