Random, interconnected crack pattern on the coating surface, caused when tensile stresses from cooling and shrinkage exceed the coating's strength. It is seen in thick or hot-sprayed ceramics, overheated fused coatings and some sealers. Unlike the controlled vertical cracks in DVC barriers, mud cracking is unplanned and opens paths for corrosive media to reach the substrate.
Chrome oxide has mud cracking all over after the grind, somebody shot it way too thick and hot.
Also heard as
- mud-cracking
- craze cracking
- crazing
Related terms
Residual stress
Stress locked into a coating and substrate after spraying, from splat shrinkage, cooling and impact.
DVC
Dense vertically cracked: a thermal barrier sprayed hot so it forms deliberate through-thickness cracks.
Cook
Booth slang for overheating a part during spraying, usually from slow traverse, short standoff or no pauses.
Sealer
A thin liquid resin brushed or soaked into a sprayed coating to fill its connected porosity.