Accession Number:

ADA516835

Title:

Role of Atomic Packing in Glass Forming Ability and Stability of Ternary and some Quaternary Bulk Metallic Glasses

Descriptive Note:

Final rept. 11 Mar 2009-25 Mar 2010

Corporate Author:

TOHOKU UNIV SENDAI (JAPAN) INST FOR MATERIALS RESEARCH

Personal Author(s):

• Louzguine-Luzgin, Dmitri V.

Report Date:

2010-03-29

Pagination or Media Count:

7.0

Abstract:

In this work we study the influence of atomic packing efficiency on glass-forming ability of bulk defined as 3-dimensional massive glassy articles with a size of not less than 1 mm in any dimension metallic glasses by the analysis of a database of ternary and quaternary bulk metallic glasses. An extensive dataset on the composition and stability critical thickness, glass-transition temperature, crystallization temperature and liquidus temperature of ternary and quaternary metallic glasses has been obtained from the literature data. The results indicate that glassy alloys compositions are distributed in a highly non-uniform way in the compositional area and tend to prefer specific values of fraction and atomic size ratios. For example in ternary alloys clear maxima are seen at about A65B15C20, A70B10C20, A65B10C25, A40B18C38, A45B17C28 and A58B13C45 compositions. Clear minimum at A50B25C25 corresponds to the A2BC compound, while A60B5C35 and A75B5C20 compositions are close to A2C and A3C binary compounds, respectively. Glass-forming ability is shown to increase with increasing the number of alloying elements. According to the statistical analysis one can anticipate that the difference in Dc among binary, ternary and quaternary alloys is meaningful which confirms the first Inoues principle for achieving high GFA. Quaternary bulk glass-forming alloys with large critical diameter in general have larger DTx than those of ternary alloys and are preferable for shaping in SCLR. As Tg and Tx for ternary and quaternary alloys nearly linearly depends on Tl, one may anticipate that it is not a coincidence but real physical meaning on structural unity of the bulk-glass-forming alloys.

Descriptors:

• *METALLIC GLASS
• *PACKING MATERIALS
• *ATOMIC PROPERTIES
• *QUATERNARY COMPOUNDS
• *TERNARY COMPOUNDS
• JAPAN
• BULK MATERIALS
• CHEMICAL COMPOSITION
• STATISTICAL ANALYSIS
• GLASS TRANSITION TEMPERATURE
• ALLOYS
• CRYSTALLIZATION
• AMORPHOUS MATERIALS
• LIQUIDS
• DATA BASES
• STABILITY

Subject Categories:

• Inorganic Chemistry
• Metallurgy and Metallography
• Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE