Compressive and Tensile Properties of Tungsten-Continuous-Fiber-Reinforced Zr-Based Amorphous Alloy Matrix Composite Fabricated by Liquid Pressing Process

Abstract

In the present study, a Zr-based amorphous alloy matrix composite reinforced with tungsten continuous fibers was fabricated without pores or defects by a liquid pressing process; the microstructures and mechanical properties of the fibers were investigated. Approximately 60 vol pct of the fibers was distributed inside the amorphous matrix, although the matrix of the composite also contained a small number of polygonal crystalline phases. The tensile strength of the composite was about 30 pct higher than that of the amorphous alloy, because of the very strong reinforcement of the tungsten fibers and because of the strong fiber/matrix interfacial bonding. The shear fracture of the amorphous matrix was significantly constrained by the fibers, and fracture proceded almost perpendicular to the tensile direction. According to the compressive test results of the composite, fracture did not take place as a one-time occurrence after the maximum strength point, but proceeded as the loading was sustained by the fibers, thereby leading to a maximum strength of 2477 MPa and a plastic strain of 1.5 pct. The fibers played an important role in improving the ductility, by interrupting the propagation of shear cracks initiated at the amorphous matrix and by taking over a considerable number of compressive loads in the area in which the cracks were formed, while the fibers themselves were buckled. These findings suggested that the liquid pressing process was useful for the development of amorphous matrix composites with improved mechanical properties.

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

“…Pressure infiltration [13,14] and liquid pressing process [15] were employed to prepare the W f /BMGCs. Zhang et al [14] reported that no reactive layer is the key to prepare the W f / BMGCs with excellent properties.…”

Correlation of Microstructure and Mechanical Properties of Tantalum-Continuous-Fiber-Reinforced Amorphous Matrix Composite Processed by Liquid Pressing

“…General processes of amorphous matrix composites include partial crystallization of amorphous alloys to disperse nanocrystallines, [11][12][13] generation of dendritic crystalline phases from the amorphous melt, [14] addition of crystalline particles to the amorphous melt, [15,16] and casting of both reinforcing fibers and amorphous alloys. [17][18][19] When amorphous matrix composites reinforced with continuous metallic fibers are processed by casting it is important to control reactions of the amorphous melt with fibers, since most metallic fibers except refractory fibers have high reactivity with the amorphous melt. Thus, in order to effectively process casting composites it is necessary to use metallic fibers having high thermal stability as reinforcements and to introduce new concept process technologies, one of which is a liquid pressing process [20] using low pressure near to the theoretically required minimum loading pressure.…”

Atomic interaction mechanism for designing the interface of W/Zr-based bulk metallic glass composites

“…The strengthes of the W fiber of 0.3 μm and the Vitreloy 1 alloy are 2200 MPa15 and about 1900 MPa79, respectively, and the calculated strength of the corresponding composite is about 2140 MPa. The difference between the theoretical and experimental strength also exists in many other reports161718. This means the compositing procedure weakens the composite's mechanical property, which becomes the main obstacle of the application of BMGCs.…”

“…This means the compositing procedure weakens the composite's mechanical property, which becomes the main obstacle of the application of BMGCs. The reasons for the gap reported before are the residual tensile stress in the amorphous matrix formed during solidification and the stress concentration at the interface caused by shear bands or cracks at the matrix17. Besides, the interdiffusion and further interfacial reaction between W fibers and active elements in the matrix, such as Zr and Ti, reduce the composite's mechanical properties significantly.…”