Dense vertically cracked, also called segmented, thermal barrier coating, made by plasma spraying zirconia with high particle and substrate temperatures so the coating is dense but splits into columns along controlled vertical cracks. The cracks open and close with thermal cycling, giving strain tolerance and allowing much thicker ceramic layers than conventional porous coatings. Crack density per unit length is a measured acceptance criterion.
Crack count on the DVC coupon is low, the part ran too cool, bump the substrate temp up.
Also heard as
- dense vertically cracked
- segmented TBC
- segmentation cracking
Related terms
Thermal barrier coating
A ceramic coating system that insulates hot-section metal parts from combustion gas temperatures.
YSZ
Yttria-stabilized zirconia: the standard ceramic for thermal barrier top coats.
Mud cracking
A network of surface cracks that looks like dried mud, from tensile stress in a coating.
Substrate temperature
The temperature of the part being coated, usually held below about 150 °C during spraying.