attach vs weld together

attach

verb
  • To win the heart of; to connect by ties of love or self-interest; to attract; to fasten or bind by moral influence; with to. 

  • To adhere; to be attached. 

  • To connect, in a figurative sense; to ascribe or attribute; to affix; with to. 

  • To come into legal operation in connection with anything; to vest. 

  • To fasten, to join to (literally and figuratively). 

weld together

verb
  • To forge a social or emotional bond between people. 

  • Used other than figuratively or idiomatically: see weld, together. 

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