ductility vs pliability

ductility

noun
  • Ability of a material to be drawn out longitudinally to a reduced section without fracture under the action of a tensile force. 

pliability

noun
  • The quality or state of being pliable; flexibility; pliableness. 

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