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The influence of decreased temperature of tensile testing on annealing-induced hardening (AIH) and deformation-induced softening (DIS) effects has been studied in an ultrafine-grained (UFG) Al–Zr alloy produced by high-pressure torsion. We show that the UFG Al–Zr alloy demonstrates a DIS effect accompanied by a substantial increase in the elongation to failure δ (up to δ ≈ 30%) depending on the value of additional straining. Both the AIH and DIS effects weaken with a decrease in the tensile test temperature. The critical deformation temperatures were revealed at which the AIH and DIS effects are suppressed. The activation energy Q of plastic flow has been estimated for the UFG Al–Zr alloy in the as-processed, subsequently annealed and additionally strained states. It was shown that the annealing decreases the Q-value from ~80 kJ/mol to 23–28 kJ/mol, while the subsequent additional straining restores the initial Q-value. Alloying with Zr results in the expansion of the temperature range of the AIH effect manifestation to lower temperatures and results in the change in the Q-value in all of the studied states compared to the HPT-processed Al. The obtained Q-values and underlying flow mechanisms are discussed in correlation with specific microstructural features and in comparison to the UFG Al.

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As seen from Chap. 3 of this book, nanostructuring of various metallic materials is a key for obtaining extraordinary multifunctional properties that are very attractive for different structural and functional applications. Materials experts have asserted that materials breakthroughs in the twentieth century required about 20 years from the time of invention to gain widespread market acceptance [1].1 Bulk nanostructured metallic materials also have been following this track. Despite a wide research started at the beginning of 1990, very significant progress in their commercialization has been made just in recent years, which is evident by the first production of advanced pilot articles from nanostructured metals and alloys with new functionality. These aspects of innovations of bulk nanostructured metallic materials processed by SPD are discussed in this chapter.Application and commercialization of bulk nanostructured metallic materials are associated with three primary points: their superior properties, their efficient fabrication, and the possibility to produce cutting-edge products from these materials. Analytical reports documented more than 100 specific market areas for nanostructured metals [2,3], and it is evident that many of these new structural and functional applications involve extreme environments where exceptional strength and improved functional properties are needed. Below are the examples of nanomaterials developments for their innovation applications in engineering and medicine. Nanostructured Ti and Ti Alloys for Biomedical EngineeringPure Ti possesses the highest biocompatibility with living organisms, but it has limited use in medicine due to its low strength.

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The paper reports on the features of low-temperature superplasticity of the heat-treatable aluminum Al-Mg-Si alloy in the ultrafine-grained state at temperatures below 0.5 times the melting point as well as on its post-deformation microstructure and tensile strength. We show that the refined microstructure is retained after superplastic deformation in the range of deformation temperatures of 120–180 °C and strain rates of 5 × 10–3 s–1–10–4 s–1. In the absence of noticeable grain growth, the ultrafine-grained alloy maintains the strength up to 380 MPa after SP deformation, which considerably exceeds the value (250 MPa) for the alloy in the peak-aged coarse-grain state. This finding opens pathways to form high-strength articles of Al-Mg-Si alloys after superplastic forming.

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