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Three high-nitrogen stainless steels with different N contents were successfully processed by equal-channel angular pressing for one pass, and their microstructures and mechanical properties were investigated. It was found that the microstructure of the billet was heterogeneous across the billet thickness, resulting in the difference in the mechanical properties due to the different deformation conditions. A relatively low strength, high uniform elongation, and high work-hardening rate for the samples at the bottom of the billet was achieved in comparison with those processed at the top. Meanwhile, it was observed that the density of deformation twins increased with the content of N; accordingly, the strength and elongation of the alloys increase with the content of N, resulting in a good strength–ductility combination.

A new parameter, i.e., tearing toughness, was employed to characterize the mechanical properties of some ductile metals (Cu, Cu–2 wt% Be, Cu–Al alloys, and some steels) by using three-leg trousers tearing tests. The experimental results demonstrate that their tearing toughness is not a physical constant and shows a close relationship with the materials’ types and microstructures. It can be inferred that the tearing toughness of different ductile metals has their respective variation range, expectantly, and may be represented by the comprehensive mechanical properties of strength and ductility for various ductile materials.