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arXiv · 2102.09906

Spinodal decomposition stabilizes plastic flow in a nanocrystalline Cu-Ti alloy

Julian M. Rosalie·Oliver Renk·Reinhard Pippan
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Abstract

A combination of high strength and reasonable ductility has been achieved in a copper-1.7 at.%titanium alloy deformed by high-pressure torsion. Grain refinement and a spinodal microstructure provided a hardness of 254 +/- 2 HV , yield strength of 800 MPa and elongation of 10%. The spinodal structure persisted during isothermal ageing, further increasing the yield strength to 890MPa while retaining an elongation of 7%. This work demonstrates the potential for spinodal microstructures to overcome the difficulties in retaining ductility in ultra-fine grained or nanocrystalline alloys, especially upon post-deformation heating where strain softening normally results in brittle behavior.

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Julian M. Rosalie, Oliver Renk, Reinhard Pippan. 2021-02-19. Spinodal decomposition stabilizes plastic flow in a nanocrystalline Cu-Ti alloy. https://arxiv.org/abs/2102.09906

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