amalgam vs soldering

amalgam

noun
  • One of the ingredients in an alloy. 

  • A combination of different things. 

  • An alloy containing mercury. 

soldering

noun
  • A method of joining two metallic surfaces by melting an alloy between them. 

  • A soldered joint. 

  • An instance of soldering. 

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