Cyclic deformation behaviour of TiAl6V4 and TiAl6Nb7 in different quasi-physiological media

✍ Scribed by B. Schwilling; C. Fleck; D. Eifler

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 558 KB
• Volume: 33
• Category: Article
• ISSN: 0933-5137
• DOI: 10.1002/1521-4052(200208)33:8<453::aid-mawe453>3.0.co;2-c

✦ Synopsis

In the present investigation the cyclic deformation behaviour of TiAl6V4 and TiAl6Nb7 was characterized in constant-amplitude and load increase tests in laboratory air and quasi-physiological media by cycle dependent mechanical hysteresis, temperature and/or corrosion potential measurements. Microstructural changes were evaluated by scanning electron microscopy for defined fatigue states and after specimen failure. In constant-amplitude tests, the alloys show pronounced cyclic softening and/or hardening. In load increase tests with strain and temperature measurements, estimation values for the endurance limit were determined which were lower than the fatigue limits determined in conventional Woehler tests to a maximum cycle number of 2 Â 10 6 . For loading in quasi-physiological media, the corrosion potential reliably indicates microstructural damage on the specimen surface.

In der vorliegenden Untersuchung wurde das Wechselverformungsverhalten von TiAl6V4 und TiAl6Nb7 in Einstufen-und Laststeigerungsversuchen an Laborluft und in quasi-physiologischen Medien mit Hilfe der Entwicklung der lastspielzahlabha Èngigen plastischen Dehnungsamplitude sowie der Probentemperatur bzw. des Korrosionspotentials charakterisiert. Fu Èr definierte Ermu Èdungszusta Ènde und nach Probenbruch wurden mikrostrukturelle Vera Ènderungen im Rasterelektronenmikroskop untersucht.