|
Influence of Austenite Grain Size on Mechanical Properties of Stainless SMA
|
Jorge Otubo1)2), Fabiana C. Nascimento3), Paulo R. Mei3), Lisandro P. Cardoso4) and Michael J. Kaufman5)
|
1) Energy and Nuclear Research Institute, Center for Materials Science and Technology
2) Faculdades Integradas de S. Paulo
3) State University of Campinas, Dept. of Materials Engineering
4) State University of Campinas, Physics Institute
5) University of Florida, Materials Science and Engineering
|
This paper presents experimental results relating the initial austenite grain size to bulk hardness, compressive yield stress (σ0.2%) and volume fraction of stress-induced ε martensite. It is shown that the bulk hardness obeys quite closely the Hall-Petch equation while the yield stress, σ0.2%, decreases with decrease of grain size, indicating that the induction of ε martensite mechanically is easier for the materials with finer grains. This fact is corroborated by the observed increase of the volume fraction of stress-induced ε martensite with decrease of grain size. Inversely, after shape recovery heating, the volume fraction of residual stress-induced ε martensite increases as the grain size increases, e.g. the increase in grain size hinders the reversible martensitic transformation.
|
Keyword: stainless shape memory alloy, martensitic transformation, mechanical properties, austenite grain size
|
Received: November 20, 2001
Accepted: April 15, 2002 ,
Published online: September 06, 2005 |
|
Copyright (c) 2005 The Japan Institute of Metals |
 Reference
,
 PDF file (J-STAGE)
,  J-STAGE
|
|
Account
Main menu
Search
