High Pressure Phase-Transformation Induced Texture Evolution and Strengthening in Zirconium Metal: Experiment and Modeling

Abstract

We studied the phase-transition induced texture changes and strengthening mechanism for zirconium metal under quasi-hydrostatic compression and uni-axial deformation under confined high pressure using the deformation-DIA (D-DIA) apparatus. It is shown that the experimentally obtained texture for ω-phase Zr can be qualitatively described by combining a subset of orientation variants previously proposed in two different models. The determined flow stress for the high-pressure ω-phase is 0.5–1.2 GPa, more than three times higher than that of the α-phase. Using first-principles calculations, we investigated the mechanical and electronic properties of the two Zr polymorphs. We find that the observed strengthening can be attributed to the relatively strong directional bonding in the ω phase, which significantly increases its shear plastic resistance over the α-phase Zr. The present findings provide an alternate route for Zr metal strengthening by high-pressure phase transformation.

In situtransmission electron microscopy study of the thermally induced formation of δ′-ZrO in pure Zr and Zr-based alloy

“…==½1120 (Trinkle et al, 2003(Trinkle et al, , 2005, which has been observed in shock-loaded Zr by TEM (Cerreta et al, 2005). Recently, a synchrotron X-ray study on high-pressureinduced texture evolution in Zr showed that both ORs can occur under high pressure (Yu et al, 2015). In our study, the same two ORs which are reported for and !…”

“…4(a). In contrast, in the parent grain which is oriented with [0110] aligned to the normal of the TEM thin foil, the OR follows (1011Þ ZrO == ð0002Þ and ½0111 ZrO ==½1120 , which is the same as another OR that is sometimes reported between -Zr/Ti and !-Zr/Ti (Usikov & Zilbershtein, 1973;Trinkle et al, 2003;Yu et al, 2015), shown in the pole figure in Fig. 4(b).…”

“…However, there are still some discrepancies in the reported OR between the phase and ! phase, even though much effort has been made over recent decades with a variety of techniques including TEM (Cerreta et al, 2005;Rabinkin et al, 1981), in situ synchrotron diffraction (Yu et al, 2015;Jacobsen et al, 2015;Zong et al, 2014;Wenk et al, 2013), and ab initio modeling (Trinkle et al, 2005(Trinkle et al, , 2003. There are two orientation relationships that have been widely reported.…”

Manganese mono-boride, an inexpensive room temperature ferromagnetic hard material

“…The relatively low hardness, typically below the value of 5 GPa, of traditional magnetic materials inevitably impede the application of traditional magnetic materials in harsh conditions91011121314. To strengthen the mechanical properties of ferromagnetic materials, fabricating composite, ageing process, doping and controlling microstructure have been attempted to enhance mechanical properties789151617. However, the mechanical properties of ferromagnetic materials still fall far short the requirements of industrial applications18.…”

Metastable phase transformation and hcp- ω transformation pathways in Ti and Zr under high hydrostatic pressures

“…[1][2][3][4][5][6][7] Their applicability is limited by the hcp (a)-simple hexagonal (x) phase transformation under high hydrostatic pressure. [4][5][6][7][8][9] The appearance of the x phase can strengthen the metal, 10,11 while it also greatly lowers its toughness and ductility. [7][8][9] Extensive research has been undertaken to identify, and possibly modify, the mechanism of the hcp-x phase transformation.…”