Improvement of MRI compatible Au-Pt-8Nb alloys through controlling the microstructure

2014 Fiscal Year Final Research Report

• Project/Area Number: 24500528
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Biomedical engineering/Biological material science
• Research Institution: The University of Tokushima
• Principal Investigator: HAMADA Kenichi 徳島大学, ヘルスバイオサイエンス研究部, 教授 (00301317)
• Research Collaborator: HONDA Eiichi ; TAKEGAWA Emi ; INUI Shihoko
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: アーチファクト / 磁化率 / MRI / Au合金 / 強度 / 加工性

Outline of Final Research Achievements

Workability of Au-5Pt-8Nb alloy ingot was insufficient and they showed serious cracks after cold-rolling. However, Au-5Pt-8Nb alloy wire was successfully produced using swaging process. Since the magnetic susceptibility of wire was slightly increased from Au-5Pt-8Nb ingot due to potential impurity elements absorbed during swaging process, the alloy composition was modified to Au-5Pt-7Nb. The ultimate strength/elongation of the wire could be changed from 540 MPa/25% to 630 MPa/13% using heat treatment. A prototype aneurysm clip could be produced from annealed soft wire. After aging treatment, the prototype clip showed the closing force required. Magnetic resonance image of the clip indicated that significant artifact was occurred around coil section of the clip. This artifact suggested that improvement of coil design was required to produce an artifact free clip.

Free Research Field

生体材料工学