▁found ▁applications ▁starting ▁in ▁the ▁ 1 9 8 0 s ▁in ▁product ▁development , ▁data ▁visual ization , ▁rapid ▁pro tot yp ing , ▁and ▁special ized ▁manufact uring . ▁Their ▁expansion ▁into ▁production ▁( job ▁production , ▁mass ▁production , ▁and ▁distributed ▁manufact uring ) ▁has ▁been ▁under ▁development ▁in ▁the ▁dec ades ▁since . ▁Indust rial ▁production ▁roles ▁within ▁the ▁metal working ▁indust ries ▁achieved ▁significant ▁scale ▁for ▁the ▁first ▁time ▁in ▁the ▁early ▁ 2 0 1 0 s . ▁Since ▁the ▁start ▁of ▁the ▁ 2 1 st ▁century ▁there ▁has ▁been ▁a ▁large ▁growth ▁in ▁the ▁sales ▁of ▁AM ▁machines , ▁and ▁their ▁price ▁has ▁dropped ▁substantial ly . ▁According ▁to ▁W oh lers ▁Associ ates , ▁a ▁consult ancy , ▁the ▁market ▁for ▁ 3 D ▁printer s ▁and ▁services ▁was ▁worth ▁$ 2 . 2   b ill ion ▁world wide ▁in ▁ 2 0 1 2 , ▁up ▁ 2 9 % ▁from ▁ 2 0 1 1 . ▁McK in sey ▁predict s ▁that ▁add itive ▁manufact uring ▁could ▁have ▁an ▁economic ▁impact ▁of ▁$ 5 5 0 ▁billion ▁ann ually ▁by ▁ 2 0 2 5 . ▁There ▁are ▁many ▁applications ▁for ▁AM ▁techn ologies , ▁including ▁architecture , ▁construction ▁( A EC ), ▁industrial ▁design , ▁autom ot ive , ▁a eros pace , ▁military , ▁engineering , ▁dent al ▁and ▁medical ▁indust ries , ▁bi ote ch ▁( human ▁t issue ▁replacement ), ▁fashion , ▁foot we ar , ▁j