Contact fatigue behavior of α-Al2O3-Ti(C,N) CVD coated WC-Co under dry and wet conditions

The response to cycling contact fatigue load of a WC-6%Co carbide coated with Ti(C,N)/α-Al2O3 CVD multilayer was investigated in dry and wet conditions. Imprints conditions were characterized by small thin cracks forming circumference at the maximum radii imprint. damaged coating totally present final imprint test. Wet indentations showcase an area where α-Al2O3 layer has been removed throughout ring but kept center indentation, suggesting that damage under is dominated degradation, associated fretting effect or tangential loads accelerating fatigue-corrosion alumina layer.