Direct Observation on the Evolution of Shear Banding and Buckling in Tungsten Fiber Reinforced Zr-Based Bulk Metallic Glass Composite

Abstract

The evolution of micro-damage and deformation of each phase in the composite plays a pivotal role in the clarification of deformation mechanism of composite. However, limited model and mechanical experiments were conducted to reveal the evolution of the deformation of the two phases in the tungsten fiber reinforced Zr-based bulk metallic glass composite. In this study, quasi-static compressive tests were performed on this composite. For the first time, the evolution of micro-damage and deformation of the two phases in this composite, i.e., shear banding of the metallic glass matrix and buckling deformation of the tungsten fiber, were investigated systematically by controlling the loading process at different degrees of deformation. It is found that under uniaxial compression, buckling of the tungsten fiber occurs first, while the metallic glass matrix deforms homogeneously. Upon further loading, shear bands initiate from the fiber/ matrix interface and propagate in the metallic glass matrix. Finally, the composite fractures in a mixed mode, with splitting in the tungsten fiber, along with shear fracture in the metallic glass matrix. Through the analysis on the stress state in the composite and resistance to shear banding of the two phases during compressive deformation, the possible deformation mechanism of the composite is unveiled. The deformation map of the composite, which covers from elastic deformation to final fracture, is obtained as well.

Penetrating Power of High-Density Tungsten Fiber/Zr-Based Metallic Glass Matrix Composite

“…However, the dynamic yield strength Y p of the high-density WF/Zr-MG is 3000 MPa, which is higher than that of 93W alloy with a strain rate of 3000 s − 1 . According to equation (7), it can be found that the penetration velocity u of the highdensity WF/Zr-MG composite penetrator is larger than that of the 93W alloy penetrator when these penetrators have the same velocity v. In other words, the penetration ability of the high-density WF/Zr-MG composite penetrator is better than that of the 93W alloy penetrator with the same penetration conditions, such as mass and impact velocity.…”

“…Due to its excellent properties, including high-density and high-dynamic compressive strength, the tungsten fiber reinforced Zr-based metallic glass (Zr 41.25 Ti 13.75 Cu 12.5 Ni 10 Be 22.5 ) matrix (WF/Zr-MG) composite is considered as a potential new generation of projectile material to replace DUA and WHA [6,7]. Lots of research on WF/Zr-MG composite, which covers material design and preparation, fracture mode, and static and dynamic mechanical properties, have been reported in the past few years [8][9][10][11].…”

“…Lots of research on WF/Zr-MG composite, which covers material design and preparation, fracture mode, and static and dynamic mechanical properties, have been reported in the past few years [8][9][10][11]. Conner et al [6,12], Du et al [13], and Chen et al [7,14] conducted penetration tests to investigate the penetration power and failure of the WF/Zr-MG composite rods.…”

On the compressive failure of tungsten fiber reinforced Zr-based bulk metallic glass composite

“…10(b), it can be seen that the splitting fracture always happens within the tungsten fiber. In our other work (Chen et al, 2014), the deformation process of this composite is investigated carefully. It was found that the splitting initiate within the tungsten fiber near the fiber/matrix interface region.…”

Effect of W volume fraction on dynamic mechanical behaviors of W fiber/Zr-based bulk metallic glass composites

“…Thermal residual stress in the W fiber was established to be under compressive stress state in the three-dimensional (3D) directions, which is beneficial to the performance improvement of the W f /BMGCs [16,17]. It was found that the W fibers yielded firstly and then transferred load to the metallic glass phase during deformation, the bonding characteristics and the interfacial status between the two phases are the key factors to determine whether the W f /BMGCs shear or split [18][19][20][21]. In addition, the failure mode of the W f /BMGCs is influenced seriously by W fiber volume fraction (V f ), the failure mode varied from shearing to longitudinal splitting with the increase of V f [22][23][24].…”