The corrosion fatigue tests were carried out for Cr-Mo steel (SCM440) by varying the stress rising time (tR), holding time (tH) and descending time (tD). In the present paper, for the case of symmetrical stress wave (tR=tH), the constitutive equation of corrosion fatigue crack growth rate, da/dN|CF, was derived explicitly in terms of tR and tH. The experimental results of corrosion fatigue crack growth rate under various stress rising and holding time conditions were found to be well expressed. The equation does not satisfy the critical condition. A more satisfied constitutive equation was derived. From this equation, it can be found that the corrosion fatigue crack growth rate is affected by the time dependent effect and the fatigue effect under the symmetrical stress wave condition. The mechanism of the tR process is controlled by the fatigue effect coupled with the time dependent effect controlling the tR process, while the tD process is controlled mainly by the time dependent effect although it includes some fatigue effect.
|Number of pages||6|
|Journal||Zairyo/Journal of the Society of Materials Science, Japan|
|Publication status||Published - 1988 Aug|
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Metals and Alloys
- Polymers and Plastics