Influences of Potential and pH on Initiation of Environment-Assisted Cracking of Ti–6Al–4V

• Haruna Takumi

  Department of Materials Science and Processing, Graduate School of Engineering, Osaka University

• Hamasaki Masaya

  Department of Materials Science and Processing, Graduate School of Engineering, Osaka University

• Shibata Toshio

  Department of Materials Science and Processing, Graduate School of Engineering, Osaka University

Bibliographic Information

Other Title

• Influences of Potential and pH on Initiation of Environment-Assisted Cracking of Ti–6Al–4V

Abstract

We have investigated the influences of potential and pH on environment-assisted cracking (EAC) of Ti–6Al–4V in aqueous solutions. The EAC test was conducted by slow strain rate technique. Solution pH was controlled from 1 to 7, and applied potential was fixed between −1.8 and +0.2 V_SHE. In the solutions of pHs 3 and 7, mechanical properties of the material was almost independent of applied potential. This means that the material shows almost no EAC susceptibility in the potential-pH region for the EAC test period. At pH 1, however, both maximum stress and fracture strain changed with applied potential, and showed minimum values at an applied potential of about −1.0 V_SHE. According to surface analyses by scanning electron microscopy and X-ray diffraction technique, some cracks and Ti hydride were detected from only the specimens fractured at about −1.0 V_SHE in the solution of pH 1. Therefore, it can be concluded that Ti–6Al–4V is most susceptible to the EAC at about −1.0 V_SHE and a pH less than 1. The EAC region was in good agreement with Ti ion stable region in a potential-pH diagram of Ti/water system, and was quite similar to that on the EAC of TiAl.

Journal

• MATERIALS TRANSACTIONS

  MATERIALS TRANSACTIONS 46 (10), 2190-2196, 2005

  The Japan Institute of Metals and Materials

Keywords

• titanium–aluminum–vanadium alloy
• environment-assisted cracking
• electrochemical potential
• solution pH
• potential-pH diagram

Details

• CRID: 1390282679227603584
• NII Article ID: 10018277607
• NII Book ID: AA1151294X
• DOI: 10.2320/matertrans.46.2190
• ISSN: 13475320
• ISSN: 13459678
• NDL BIB ID: 7487810
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I7487810
• Web Site: https://www.jstage.jst.go.jp/article/matertrans/46/10/46_10_2190/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed