create a summary of CI.INT BOULTON \VALL STREET IOURNAL S1}\FF tionai manufacturing materials. Gartner Inc. analyst Pete Basiliere said he expects the costs ofsuch materials lvill fall as demand for 3-D printing increases. Rcsearch firm Wohlers Associates Inc. said the market has experienced a compound annual growth rate of e9.,1 per cent in eorr. Giobal revenue from 3-l) printers is expected to hit $3.7- billion (U.S.) in zor5, up fr.om $e.a-billion in:orz. tlere is how thesc three companies use 3-D printing: and have the part in hours or minutes. ford is using 3-D printing to prototype automobiie parts for test vehicles, which it has been doing since the rg8os. ford engineers use industrial-grade machines that cost as much as $r-rnillion to produce prototypes of cylinder heads, brake rotors, and rear axles in less time than traditional manufacturing methods, said Paul Susalla, scction super.r,-isor of rapid manufacturing at Ford. Using 3-D prinfing, fordsaves about one month of production time to create a casting for a prototype cylinder head for its Eco, Boost family of engines. This complex part includes numerous ports, ducts, passages and valves to manage fuel and air flow. Mr. Susalla said the traditional casting method, which requires designing