Patent ID: 6939505

Claim:
A method for fabricating an article having passages therethrough, the method comprising the steps of: a. providing a fixture that defines a cavity; b. providing a plurality of elongated, core members; c. arranging said core members in said cavity in a pattern having each of said core members spaced away from any other core member; d. introducing matrix forming material into said cavity, and into spaces between and surrounding said core members, said core members having been coated with a core release coating before said step of introducing matrix material, said coating comprising an inner layer that is adjacent said core member and an outer layer that surrounds said inner layer, said matrix forming material being a material that wets said outer coating layer material; e. maintaining said fixture containing said matrix forming material and said core members, under conditions in which said matrix forming material substantially fills all of said spaces between and surrounding said core members and said cavity, such that said core members are substantially fully surrounded by matrix forming material; f. maintaining said fixture under conditions such that said matrix forming material becomes a unitary body surrounding said core members; g. removing said unitary body and surrounded core members from said fixture; and h. pulling said core members out from said unitary body, said coating inner layer having been selected to prevent bonding of said unitary body formed from matrix forming material to said core members, by being non-wetting with respect to at least one of the outer coating layer and an outer surface of the core members, whereby a channel remains where each of said removed core members had been arranged.