Residual Stresses in Shot Peened Grey and Compact Iron

• In this paper grey and compact cast irons with a pearlitic matrix are investigated after shot peening with twelve unique combinations of parameters, namely shot size, intensity and coverage, followed by residual stress measurements and evaluations. Cylindrical test samples were cut out from real cylinder heads and polished on the top flat surface to decrease effects from cutting. Residual stresses and the affected depth from the different peening conditions varied between -245 to -565 MPa and from 280 μm to 770 μm in depth. By an increase in shot size or intensity or coverage resultant surface compressive stresses will decrease whereas the affected depth increases with increasing intensity. The increased affected depth is as a result from the increased extent and magnitude of plastic deformation. The compacted cast iron was more affected than the grey cast iron, meaning that the same shot peening parameters resulted in both higher compressive stresses and larger deformation depth.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Materialteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering (hsv//eng)

Keyword

Residual stress

FWHM

cast iron

shot peening

x-ray diffraction

Publication and Content Type

vet (subject category)

ovr (subject category)