Boss formability of a Zr-based bulk metallic glass

A thermoplastic forming map of a Zr-based bulk metallic glass

“…shear transformation zones), and facilitates the formability. The similar effect of temperature on formability was also found in previous work [48][49][50][51]53]. However, when the strain rate keeps increasing, the strain rate sensitivity of FVC appears again, resulting in a transition from temporal homogeneity to inhomogeneity.…”

“…6: a fully filled regime in the bottom right-hand corner (corresponding to low strain rates or/ and high temperatures), a non-filled regime in the top left-hand corner (corresponding to high strain rates or/ and low temperatures) and a partially filled regime in between. This forming map can be compared to the deformation maps at various strain rates and temperatures in previous works [4,[49][50][51]53], implying that there exists a close correlation between formability and deformation behavior.…”

“…For instance, this transition was found to result in a dramatic decrease in tensile extensibility in a Pd-based BMG [48]. In particular, it was reported that Newtonian flow corresponding to significant structural rearrangement during TPF assists viscous flow with less thermal dissipation, and enhances the high-temperature formability of BMGs [49][50][51][52]. Accordingly, the exact relationship between the formability and the flow characteristic of BMGs during TPF is still unclear [4,[48][49][50]53].…”

Blow Molding Process Optimization of Amorphous Alloy Tube Blank Based on DEFORM Software

“…Now, setting the die inlet diameter D=10mm, die transition fillet radius R d =1mm and employing = 3 σ η⋅ ε as the constitutive equation, the molding results of plate blanks with different viscosity η and under different blowing pressure P are analyzed systemly in this article. In this section, in order to research the influence of thickness distribution of plate blank on the formability of the tube blank, set the material viscosity η=3.1× 10 6 Pa s, blowing pressure P=2.0×10 5 Pa and a series of simulations are carried out based on DEFORM software. Molding comparison between upward protruding and downward protruding plate blanks.…”

“…All kinds of bulk metallic glasses (BMGs) of Zr-, Fe-, Co-, Pd-, Pb-, Pt-, Mg-, Ti-, Ni-, Cu-based and rare earth-based of La, Ce and so on have been developed in recent years [1,2]. However, by comparison with the basic scientific research of material properties, researches about molding process technology and applied research are relatively weak and most amorphous parts produced are flat and uniform cross-section [3][4][5]. So, in recently years, blow molding is explored to process amorphous shell parts and containers with complex curved surfaces both at home and abroad, among which the research about Zr-BMGs by Jan Schroers of Yale University is the most representative one.…”