Microstructural and mechanical behavior of highly deformed Al-Sn alloys

Tensile strength and microstructural evolution were evaluated for the deformation processed metal-metal composites of Al-X vol.% Sn, where X = 3.96, 16.32, 20. Samples were prepared by casting, and deformed by cold rolling. The material was characterized by scanning electron microscopy and focused ion beam. In the case of larger true strains η > 5, the composite presents an unexpected increase in tensile strength compared to the rule of mixtures. During cold rolling, the Sn phase developed a lamellar morphology and geometrical aspects, as its separation and thickness were correlated with the tensile strength of the composite. A study of the peak broadening was made by using X-ray diffraction, in order to measure the microstrains inside the composite, and correlate them with the macroscopic strength.