Improvement of fatigue endurance of welded S355 J2 structural steel by severe shot peening

ABSTRACT

This work deals with the fatigue resistance of welded joints manufactured from EN S355 J2 structural steel and the possibility of improving fatigue characteristics by the severe shot peening (SSP) surface treatment. Fatigue testing was carried out by the rotating bending test on specimens manufactured from the base material (BM), welded material and welded material treated by SSP. Results have shown big scatter in obtained results from as-welded material and overall reduction of fatigue endurance when compared to the BM. SSP applied on the welded joints has reduced the scatter of experimental data and increased the fatigue strength. Obtained results of fatigue tests are compared, discussed and supported by correlation with results of additional experiments, e.g. metallographic analyses, microhardness tests, residual stresses measurements and surface roughness measurement.

KEYWORDS:

• Steel
• weld
• fatigue
• endurance
• improving
• severe-shot-peening

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Mario Guagliano http://orcid.org/0000-0003-1958-3974

Otakar Bokůvka http://orcid.org/0000-0001-9928-2332

Libor Trško http://orcid.org/0000-0002-9696-6939

Additional information

Funding

This research was supported by European project: Research Centre of the University of Žilina 2nd phase [ITMS 26220220183], the Slovak Research and Development Agency under the contract No. [APVV-14-0096] and [APVV-15-0120], Scientific Grant Agency of the Ministry of Education, Science and Sports of the Slovak Republic and Slovak Academy of Sciences, grant No.: [1/0123/15] and [1/0720/14].