skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Intermixing of a system with positive heat of mixing at high strain rates

Abstract

This paper investigates a mode of mechanically driven alloying of elements that are otherwise immiscible at temperatures well below the equilibrium melting point. Using molecular dynamics simulations, we have studied the alloying between Ag and Cu, a positive-heat-of-mixing (+{Delta}H) binary system with little solid solubility near ambient temperature, during high strain rate deformation at temperatures {le}600 K. Above a critical strain rate, both elements undergo mechanical melting into undercooled liquids, which are miscible at 600 K due to the reduced magnitude of the +{Delta}H in the liquid state compared with that in the crystalline state. The nonequilibrium deformation maintains the melt state and assists the intermixing reaction between elemental Ag and Cu through stress-directed atomic flow. Upon unloading, the intermixed amorphous Ag-Cu crystallizes towards a supersaturated fcc solid solution. The scheme described is a process of low-temperature amorphization and intermixing of elements, and as such differs from the well-known liquid quench route that starts from an already-mixed liquid alloy at high temperatures.

Authors:
;
Publication Date:
Sponsoring Org.:
(US)
OSTI Identifier:
40203507
Resource Type:
Journal Article
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 63; Journal Issue: 22; Other Information: DOI: 10.1103/PhysRevB.63.224205; Othernumber: PRBMDO000063000022224205000001; 061121PRB; PBD: 1 Jun 2001; Journal ID: ISSN 0163-1829
Publisher:
The American Physical Society
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALLOYS; AMBIENT TEMPERATURE; DEFORMATION; MELTING; MELTING POINTS; MIXING HEAT; SOLID SOLUTIONS; SOLUBILITY; STRAIN RATE; UNLOADING

Citation Formats

Sheng, H W, and Ma, E. Intermixing of a system with positive heat of mixing at high strain rates. United States: N. p., 2001. Web. doi:10.1103/PhysRevB.63.224205.
Sheng, H W, & Ma, E. Intermixing of a system with positive heat of mixing at high strain rates. United States. doi:10.1103/PhysRevB.63.224205.
Sheng, H W, and Ma, E. Fri . "Intermixing of a system with positive heat of mixing at high strain rates". United States. doi:10.1103/PhysRevB.63.224205.
@article{osti_40203507,
title = {Intermixing of a system with positive heat of mixing at high strain rates},
author = {Sheng, H W and Ma, E},
abstractNote = {This paper investigates a mode of mechanically driven alloying of elements that are otherwise immiscible at temperatures well below the equilibrium melting point. Using molecular dynamics simulations, we have studied the alloying between Ag and Cu, a positive-heat-of-mixing (+{Delta}H) binary system with little solid solubility near ambient temperature, during high strain rate deformation at temperatures {le}600 K. Above a critical strain rate, both elements undergo mechanical melting into undercooled liquids, which are miscible at 600 K due to the reduced magnitude of the +{Delta}H in the liquid state compared with that in the crystalline state. The nonequilibrium deformation maintains the melt state and assists the intermixing reaction between elemental Ag and Cu through stress-directed atomic flow. Upon unloading, the intermixed amorphous Ag-Cu crystallizes towards a supersaturated fcc solid solution. The scheme described is a process of low-temperature amorphization and intermixing of elements, and as such differs from the well-known liquid quench route that starts from an already-mixed liquid alloy at high temperatures.},
doi = {10.1103/PhysRevB.63.224205},
journal = {Physical Review B},
issn = {0163-1829},
number = 22,
volume = 63,
place = {United States},
year = {2001},
month = {6}
}