A study of debris and wear damage resulting from fretting of Incoloy 800 steam generator tubes against AISI Type 304 stainless steel

S. SORIA; A. TOLLEY; ALEJANDRO YAWNY

WEAR

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2016 vol. 368 p. 219 - 229

0043-1648

Wear damage and resulting triboparticles corresponding to fretting of Incoloy 800 steam generator tubes against AISI 304 pads were characterized in experiments performed in air at room temperature in a 90° cross cylinder configuration. Relative displacement amplitudes of 70, 116 and 160 mm under a normal contact load of 3574 N were considered in experiments performed up to 106 cycles. The topography and dimensions of the resulting scars on surfaces were characterized using light microscopy and scanning electron microscopy. The morphology, size and crystal structure of the debris detached during the test were determined by transmission electron microscopy and energy dispersive X-ray spectroscopy. It was verified that gross slip was the prevailing running fretting condition in all cases, while the characteristics of the scar surface layer and the corresponding wear mechanisms were found to depend on the amplitude of the relative displacement. Debris consisted in agglomerations of nano-crystalline oxide particles sized between 5 and 20 nm. The crystal structure of debris was found to depend on the displacement amplitude. For 70 mm and 116 mm, NiO, (Fe,Cr)2O3 and (Ni,Fe)(Fe,Cr)2O4 were found, while theformation of (Fe,Cr2)O3 and (Ni, Fe)(Fe,Cr)2O4 was verified for a displacement amplitude of 160 mm.