Thermodynamics analysis of the martensitic transformation in NiTi; 1: Effect of heat treatments on transformation behavior

Journal Article · Fri Jul 01 04:00:00 EDT 1994 · Acta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-7151(94)90318-2· OSTI ID:7175726

Liu, Y; McCormick, P G ^[1]

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1. Univ. of Western Australia, Nedlands (Australia). Dept. of Mechanical and Materials Engineering

The effect of heat treatment on the martensitic transformation behavior of NiTi has been investigated. Transformation temperature measurements are interpreted in terms of the chemical, elastic and irreversible components of the overall transformation free energy change. It is shown that the occurrence of a two-stage parent-R-martensite transformation on cooling and a single-stage reverse transformation in specimens annealed at intermediate temperature is a consequence of the irreversible energy loss associated with the martensitic transformation. The increase in the R transformation temperature in specimens heat treated at low temperature is shown to result from changes to the reversible, elastic or chemical, components of the transformation free energy change.

• OSTI ID: 7175726
• Journal Information: Acta Metallurgica et Materialia; (United States), Journal Name: Acta Metallurgica et Materialia; (United States) Vol. 42:7; ISSN 0956-7151; ISSN AMATEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
CRYSTAL-PHASE TRANSFORMATIONS
ELASTICITY
ENERGY
FREE ENERGY
INTERMETALLIC COMPOUNDS
MECHANICAL PROPERTIES
NICKEL ALLOYS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SHAPE MEMORY EFFECT
TENSILE PROPERTIES
THERMODYNAMIC PROPERTIES
THERMOELASTICITY
TITANIUM ALLOYS