Determination of Preferred Morphology of Self-Accommodating Martensite in Ti-Nb-Al Shape Memory Alloy Using Optical Microscopy

Masatoshi Ii; Masaki Tahara; Hideki Hosoda; Shuichi Miyazaki; Tomonari Inamura

doi:10.4028/www.scientific.net/AMR.922.260

Paper Titles

Preparatory Electrodeposition Process for High Purity Bulk Aluminum
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Structural Analysis of Shape Memory Gel
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Optimization of a Closed Die Forging Process to Manufacture a Gear Wheel by the Use of a Response Surface Model
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Determination of Preferred Morphology of Self-Accommodating Martensite in Ti-Nb-Al Shape Memory Alloy Using Optical Microscopy
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Compression of Single-Crystal Micropillars of the Γ Intermetallic Phase in the Fe-Zn System
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Polymer/Metal Joining with Carbon Fibers with High Resistance to Pull-Out Induced by Huge Friction Force Generated by Extremely Broad Total Interface Area
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X-Ray Residual Stress Analysis of Nickel Base Alloys
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Effect of Process Parameters on Friction Surfaced Coating Dimensions
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HomeAdvanced Materials ResearchAdvanced Materials Research Vol. 922Determination of Preferred Morphology of...

Determination of Preferred Morphology of Self-Accommodating Martensite in Ti-Nb-Al Shape Memory Alloy Using Optical Microscopy

Abstract:

The preferred morphology of self-accommodation (SA) microstructure in a Ti-Nb-Al shape memory alloy was investigated by the evaluation of the frequency distribution of the habit plane variant (HPV) clusters using in-situ optical microscopy. The observed HPV clusters were classified into two different types; one is the cluster connected by the {111}_o type I twin (Type I) and the other is connected by the <211>_o type II twin (Type II). The total fractions of the Type I and Type II clusters were 52% and 48%, respectively. The incompatibility at junction planes (JPs) of the two clusters was almost the same among these clusters. However, most of the larger martensite plates (> 50μm) formed Type I cluster at the later stage of the reverse martensitic transformation, i.e., at the early stage of the forward transformation upon cooling. The ratio of the fraction of Type I and II is almost 2:1 at the early stage of the forward transformation.