Tensile ductility of extrinsically toughened intermetallics

Journal Article · Tue Feb 01 04:00:00 EST 1994 · Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States)

DOI:https://doi.org/10.1007/BF02647975· OSTI ID:5263724

Chan, K S ^[1]

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1. Southwest Research Inst., San Antonio, TX (United States)

A theoretical analysis based on crack instability is presented to elucidate factors effecting the tensile ductility of intermetallics that are toughened by extrinsic mechanisms and resistance-curve effects. The analytical results indicate that extrinsic-toughening mechanisms are ineffective in imparting tensile ductility in brittle intermetallics. The plastic strain at the onset of unstable fracture is generally controlled by the initiation toughness, K[sub IC], except for materials with a high-tearing modulus, T[sub R]. The consequence is that tensile ductility increases with the initiation toughness, K[sub IC], but is unrelated to the K value measured at the peak load or the T[sub R] value for materials with low- to intermediate-tearing resistance (e.g., T[sub R]<18 for K[sub IC] = 10 MPa[radical]m). Application of the model to a two-phase TiAl alloy reveals good agreement between theory and experiment. This finding indicates that tensile ductility in brittle intermetallics can be imparted more effectively by intrinsic-toughening mechanisms than by extrinsic ones.

• OSTI ID: 5263724
• Journal Information: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States), Journal Name: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States) Vol. 25:2; ISSN 0360-2133; ISSN MTTABN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals &amp; Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
DATA
DUCTILITY
FRACTURE PROPERTIES
INFORMATION
INTERMETALLIC COMPOUNDS
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
NUMERICAL DATA
TENSILE PROPERTIES
THEORETICAL DATA
TITANIUM ALLOYS