scholarly journals Alloy Design, Thermodynamics, and Electron Microscopy of Ternary Ti-Ag-Nb Alloy with Liquid Phase Separation

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5268
Author(s):  
Takeshi Nagase
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Phase Separation ◽  
Liquid Phase ◽  
Alloy System ◽  
Liquid Phase Separation ◽  
Mixing Enthalpy ◽  
Transmission Electron ◽  
Melt Spun ◽  
Melt Spun Ribbons

The Ti–Ag alloy system is an important constituent of dental casting materials and metallic biomaterials with antibacterial functions. The binary Ti–Ag alloy system is characterized by flat liquidus lines with metastable liquid miscibility gaps in the phase diagram. The ternary Ti–Ag-based alloys with liquid phase separation (LPS) were designed based on the mixing enthalpy parameters, thermodynamic calculations using FactSage and Scientific Group Thermodata Europe (SGTE) database, and the predicted ground state diagrams constructed by the Materials Project. The LPS behavior in the ternary Ti–Ag–Nb alloy was investigated using the solidification microstructure analysis in arc-melted ingots and rapidly solidified melt-spun ribbons via trans-scale observations, combined with optical microscopy (OM), scanning electron microscopy (SEM) including electron probe micro analysis (EPMA), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM). The solidification microstructures depended on the solidification processing in ternary Ti–Ag–Nb alloys; macroscopic phase-separated structures were observed in the arc-melted ingots, whereas fine Ag globules embedded in the Ti-based matrix were observed in the melt-spun ribbons.

Metastable Phases and Defect Microstructures in Melt-Spun Ribbons of Nb3Al

1990 ◽  
Vol 209 ◽  
Author(s):  
M. Aindow ◽  
J. Shyue ◽  
T.A. Gaspar ◽  
H.L. Fraser
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Nominal Composition ◽  
Partial Dislocations ◽  
Transmission Electron ◽  
Melt Spun ◽  
B2 Phase ◽  
Melt Spun Ribbons ◽  
Defect Microstructures ◽  
A15 Phase

ABSTRACTThe phases and defects produced in a binary alloy, with nominal composition Nb-18at.% Al, have been studied using transmission electron microscopy (TEM). In addition to the equilibrium A15 phase (Nb3Al) a previously unreported Nb-rich B2 phase is present. A significant number of grow-in dislocations were observed in the A15 phase, these have b= a<100> and are predominantly screw on character. They are dissociated into two partial dislocations which bound a stacking fault according to the reaction;<100> → > 1/2 <100> + SF + 1/2 <100>The habit plane of the fault is shown to be {012}. These observations are compared with previous studies performed on the isostructual compound V3Si. The consequences of the observed dissociation for the plastic deformation of Nb3Al are discussed.

New method for the production of bulk amorphous materials of Nd–Fe–B alloys

2005 ◽  
Vol 20 (3) ◽  
pp. 563-566 ◽  
Author(s):  
Tetsuji Saito ◽  
Hiroyuku Takeishi ◽  
Noboru Nakayama
Keyword(s):  
Electron Microscopy ◽  
Amorphous Materials ◽  
Room Temperature ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
Bulk Materials ◽  
X Ray ◽  
Transmission Electron ◽  
Melt Spun ◽  
Melt Spun Ribbons

We report a new compression shearing method for the production of bulk amorphous materials. In this study, amorphous Nd–Fe–B melt-spun ribbons were successfully consolidated into bulk form at room temperature by the compression shearing method. X-ray diffraction and transmission electron microscopy studies revealed that the amorphous structure was well maintained in the bulk materials. The resultant bulk materials exhibited the same magnetic properties as the original amorphous Nd–Fe–B materials.

Sign in / Sign up

Export Citation Format

Share Document