brittleness vs friability

brittleness

noun
  • The state of being brittle; aptness to break; fragility. 

  • The property by virtue of which a material is fractured without appreciable deformation by the application of load. 

friability

noun
  • The quality of being friable, or easily broken, crumbled, or reduced to powder; friableness. 

How often have the words brittleness and friability occurred in a corpus of books? (source: Google Ngram Viewer )