Enhancing strength and ductility via crystalline-amorphous nanoarchitectures in TiZr-based alloys

Abstract

Crystalline-amorphous composite have the potential to achieve high strength and high ductility through manipulation of their microstructures. Here, we fabricate a TiZr-based alloy with micrometer-size equiaxed grains that are made up of three-dimensional bicontinuous crystalline-amorphous nanoarchitectures (3D-BCANs). In situ tension and compression tests reveal that the BCANs exhibit enhanced ductility and strain hardening capability compared to both amorphous and crystalline phases, which impart ultra-high yield strength (~1.80 GPa), ultimate tensile strength (~2.3 GPa), and large uniform ductility (~7.0%) into the TiZr-based alloy. Experiments combined with finite element simulations reveal the synergetic deformation mechanisms; i.e., the amorphous phase imposes extra strain hardening to crystalline domains while crystalline domains prevent the premature shear localization in the amorphous phases. These mechanisms endow our material with an effective strength–ductility–strain hardening combination.

Crystalline–Amorphous Nanostructures: Microstructure, Property and Modelling

“…Analogous to metallic alloy with precipitates, crystalline or amorphous nanoparticles can form in amorphous or crystalline matrix, producing crystalline–amorphous dual-phase nanocomposites [ 60 , 62 , 63 , 73 ]. Since the non-equilibrium fabrication process of MGs requires fast cooling during rapid solidification or sputtering deposition, nanocrystalline phase can form and grow in MG matrix via manipulating cooling rate, annealing temperature/time and adjusting composition [ 62 , 103 , 104 , 105 ]. Ming et al [ 62 ] synthesized TiZr-based crystalline–amorphous composites by melt spinning with a mediate cooling rate of ~10 6 K/s, which consists of micro-sized equiaxed grains and nano-width amorphous grain boundary.…”

“…Since the non-equilibrium fabrication process of MGs requires fast cooling during rapid solidification or sputtering deposition, nanocrystalline phase can form and grow in MG matrix via manipulating cooling rate, annealing temperature/time and adjusting composition [ 62 , 103 , 104 , 105 ]. Ming et al [ 62 ] synthesized TiZr-based crystalline–amorphous composites by melt spinning with a mediate cooling rate of ~10 6 K/s, which consists of micro-sized equiaxed grains and nano-width amorphous grain boundary. Notably, each grain displays crystalline–amorphous nanostructure comprising nanosized metastable crystalline (~36 nm) and amorphous (~25 nm) phases that are arranged in the form of 3D-interconnected nano-bands ( Figure 5 ).…”

“…In contrast to the brittle intermetallic compound, the amorphous nanoparticles as second phase can co-deform with metallic matrix, enhancing strength while maintaining large deformability [ 60 ]. In addition, the ductile nanosized crystal or dendrites in amorphous matrix can inhibit nucleation/propagation of shear bands and co-deformed with amorphous matrix, improving plasticity of amorphous materials [ 47 , 61 , 62 , 63 ]. Given the superior radiation tolerance exhibited in amorphous ceramic alloys, crystalline metal/amorphous ceramic composites have potential applications in extreme irradiation environments due to better heat conductivity and improved thermo-mechanical properties [ 64 , 65 , 66 ].…”

“…Based on characteristic microstructures, the reported crystalline–amorphous dual-phase nanocomposite system includes crystalline–amorphous nanolaminates [ 55 , 56 , 70 , 71 ], crystal–amorphous core–shell structures [ 13 , 14 , 53 , 72 ] and crystal- or amorphous-based dual-phase nanocomposites [ 60 , 62 , 63 , 73 ]. In this article, we briefly review crystalline–amorphous dual-phase nanocomposites with the three typical microstructures.…”

Research progress of novel zirconium alloys with high strength and toughness

“…Zr-based amorphous has a wide range of application prospects. According to Ming et al [49], TiZr-based alloys can be effectively strengthened by crystallization-amorphous nanostructures through in situ tensile and compression experiments and finite element simulations. The currently developed prepared armor-piercing warhead 0, with self-sharpening properties similar to those of depleted uranium armor-piercing ammunition and promising to surpass them, is a promising and ideal material.…”