Microstructure and Compressive Properties of <I>In-Situ</I> Martensite CuZr Phase Reinforced ZrCuNiAl Metallic Glass Matrix Composite

Abstract

In-situ micro-level martensite CuZr phase reinforced Zr 50:5 Cu 27:45 Ni 13:05 Al 9 metallic glass matrix composite was synthesized by copper mold casting. Microstructure and compressive properties of the composite are investigated. The martensite CuZr phase possesses numerous coherent twin boundaries, and holds strong interfacial cohesion with the matrix. They both effectively induce the seeding and branching of shear bands during compression. The compressive properties of the composite are therefore improved. The fracture strength and plastic strain of composite with a diameter of 3 mm is up to 2190 MPa, 5.7% respectively.

RETRACTED: Development of Bulk Metallic Glasses and their Composites by Additive Manufacturing - Evolution, Challenges and a Proposed Novel Solution

“…It formed in-situ during solidification thus giving birth to the "so-called" family of in-situ dendrite / metallic glass matrix composites. These materials are formed as a result of conventional solute partitioning mechanisms as observed in other metallurgical alloys resulting in the copious formation of a ductile phase β-(Ti-Zr-Nb) in case of Ti-based composites [12], Cu-Zr B2 spheroid intermetallic in the case of Zr-based composites without Be [94,98,[183][184][185][186] or transformed B2 (B19' martensite) in the case of Zr-Cu-Al-Co shape memory bulk metallic glass matrix composites (a special class of BMGMCs) [21,185,[187][188][189][190][191]) predominantly (not always) in the form of three dimensional dendrites or spheroids emerging directly from the liquid during solidification. Devitrification and formation of ordered structures in these alloys can be explained by the help of "phase separation" or "quenched in" nuclei [192][193][194][195][196].…”

Metallic glass matrix composites

“…Recently, this kind of composites has been successfully synthesized by different research groups, and the distinguished work hardening was achieved regardless of tensile or compressive loadings [123][124][125][126][127][128][129][130][131][132][133]. The parent phase has a size of about several microns, similar to that of dendrites or Ta-particles and larger than that of nanoprecipitates within the amorphous matrix [74][75][76][77][78]134].…”

“…The parent phase has a size of about several microns, similar to that of dendrites or Ta-particles and larger than that of nanoprecipitates within the amorphous matrix [74][75][76][77][78]134]. Up to now, the discovered parent phase in the metallic glass matrix is the equiatomic CuZr intermetallic compound [123][124][125][126][127][128][129][130][131][132][133], which exhibits the same shape-memory effect as Ni-Ti and Cu-Zn-Al alloys [135]. The equiatomic CuZr phase has different metastable structures, i.e., the high-temperature B2 CuZr phase with a cubic primitive structure (Pm-3m), and monoclinic martensites (P2 1 /m and Cm), as schematically shown in During plastic deformation or cooling, the B2 CuZr phase transforms into martensites, and is not stable at room temperature for most of CuZr-based alloys.…”

Microstructure evolution and mechanical properties of Nb-alloyed Cu–Zr–Al–Ni large-sized metallic glass composites

“…Figure 6(b,d,f) shows the fracture morphologies of the (Cu 0.47 Zr 0.47 Al 0.06 ) 99 Ni 1 , (Cu 0.47 Zr 0.47 Al 0.06 ) 98.5 Ni 1 Nb 0.5 and (Cu 0.47 Zr 0.47 Al 0.06 ) 98 Ni 1 Nb 1 alloys. In Figure 6(b,d), there are an amount of the vein-like patterns which are typical fracture features of BMGs [25,26], however, vein-like patterns in Figure 6(d) are distinctly thinner and denser compared with Figure 6(b). Moreover, lots of molten droplets marked by the black circle in Figure 6(d) are observed on the fracture surface, which contributes to the enhancement of plasticity due to the energy releases during the plastic deformation [27].…”