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Title: Stability of Ni-bsed bulk metallic glasses

Abstract

Several ternary (Ni{sub x}Nb{sub y}Sn{sub z}) refractory alloy glasses (RAGs) were studied at elevated temperatures in order to assess the stability of the amorphous state, i.e. devitrification, and to identify subsequent phase transformations in these materials. differential scanning calorimetry (DSC) experiments indicated a complex phase transformation sequence with several distinct crystallization and melting events being recorded above the glass transition temperature, T{sub g}. Below T{sub g} the RAG samples were studied with an in situ environmental X-ray furnace facility, which allowed step-wise isothermal ramping experiments commencing at a temperature below the reduced temperature of T/T{sub g} {approx} 0.80. Distinct crystalline phases were observed when T/T{sub g} {approx} 0.84 for ternary RAG alloys, while similar experiments on Zr-based Vit 106 glass alloys did not reveal any apparent phase separation until T/T{sub g} {approx} 0.96. The phase separation kinetics followed an Arrhenius type of relationship with Ni{sub 3}Sn, and Nb{sub 2}O{sub 5} being the principle crystalline precipitates.

Authors:
 [1];  [2];  [2];  [1]
  1. University of Michigan
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); High Temperature Materials Laboratory
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1003610
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Non-Crystalline Solids; Journal Volume: 352; Journal Issue: 10.1016
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; AMORPHOUS STATE; CALORIMETRY; CRYSTALLIZATION; FURNACES; GLASS; HEAT RESISTING ALLOYS; KINETICS; MELTING; METALLIC GLASSES; PHASE TRANSFORMATIONS; STABILITY; TRANSITION TEMPERATURE

Citation Formats

Tokarz, Michelle L, Speakman, Scott A, Porter, Wallace D, and Bilello, John C. Stability of Ni-bsed bulk metallic glasses. United States: N. p., 2006. Web. doi:10.1016/j.jnoncrysol.2006.05.012.
Tokarz, Michelle L, Speakman, Scott A, Porter, Wallace D, & Bilello, John C. Stability of Ni-bsed bulk metallic glasses. United States. doi:10.1016/j.jnoncrysol.2006.05.012.
Tokarz, Michelle L, Speakman, Scott A, Porter, Wallace D, and Bilello, John C. Sun . "Stability of Ni-bsed bulk metallic glasses". United States. doi:10.1016/j.jnoncrysol.2006.05.012.
@article{osti_1003610,
title = {Stability of Ni-bsed bulk metallic glasses},
author = {Tokarz, Michelle L and Speakman, Scott A and Porter, Wallace D and Bilello, John C},
abstractNote = {Several ternary (Ni{sub x}Nb{sub y}Sn{sub z}) refractory alloy glasses (RAGs) were studied at elevated temperatures in order to assess the stability of the amorphous state, i.e. devitrification, and to identify subsequent phase transformations in these materials. differential scanning calorimetry (DSC) experiments indicated a complex phase transformation sequence with several distinct crystallization and melting events being recorded above the glass transition temperature, T{sub g}. Below T{sub g} the RAG samples were studied with an in situ environmental X-ray furnace facility, which allowed step-wise isothermal ramping experiments commencing at a temperature below the reduced temperature of T/T{sub g} {approx} 0.80. Distinct crystalline phases were observed when T/T{sub g} {approx} 0.84 for ternary RAG alloys, while similar experiments on Zr-based Vit 106 glass alloys did not reveal any apparent phase separation until T/T{sub g} {approx} 0.96. The phase separation kinetics followed an Arrhenius type of relationship with Ni{sub 3}Sn, and Nb{sub 2}O{sub 5} being the principle crystalline precipitates.},
doi = {10.1016/j.jnoncrysol.2006.05.012},
journal = {Journal of Non-Crystalline Solids},
number = 10.1016,
volume = 352,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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