The Use of Double Surface Treatments to Optimize the Fatigue Life of Components Made on Structural Steels
Autor: | Elvira Segurado, F.Javier Belzunce |
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Rok vydání: | 2016 |
Předmět: |
0209 industrial biotechnology
Materials science Laser peening Metallurgy technology industry and agriculture Peening vibratory finishing 02 engineering and technology General Medicine Surface finish Shot peening double tretaments Stress (mechanics) 020303 mechanical engineering & transports 020901 industrial engineering & automation grit blasting 0203 mechanical engineering Residual stress shot peening fatigue Stress intensity factor Engineering(all) Stress concentration |
Zdroj: | Procedia Engineering. 160:239-245 |
ISSN: | 1877-7058 |
DOI: | 10.1016/j.proeng.2016.08.886 |
Popis: | High intensity shot peening treatments have been combined with other different second treatments, such as low intensity shot peening, vibratory finishing and grit blasting with fine alumina powders, in order to optimize the fatigue life of a medium-alloyed, quenched and tempered, structural steel with a very high strength (2000 MPa). Single low intensity shot peening treatments using ceramic balls were also used with the same objective. Roughness and residual stress profiles were measured, while the fatigue behavior was analyzed using a rotating bending fatigue equipment. Fracture surfaces were also analyzed in a scanning electron microscope (SEM) and the location of the fatigue crack initiation was detected. Although the maximum stress in our fatigue tests is always applied on the surface of the specimen, the appropriate surface treatment combinations were able to optimize the fatigue response of the steel until the point where the fatigue crack initiated in the specimen interior (subsurface nucleation), due to the microstructural stress concentration provided by small alumina inclusions present in the microstructure of the steel. The amplitude of the stress intensity factor necessary to propagate fatigue cracks in the studied steel and the intrinsic stress intensity factor threshold, ΔK th , were finally obtained. |
Databáze: | OpenAIRE |
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