Method of making acoustic holes using uv curing masking material

Abstract

A method of forming acoustic holes in a composite sound-insulating material includes creating a image of at least a portion of an array of holes and transferring the image to an ultraviolet (UV) radiation transparent medium. The method continues with positioning the medium in contact with a UV-curable mask and exposing the medium-covered mask to UV radiation to cure the UV-exposed areas. The method further includes removing the uncured mask material to create an abrading mask that includes a plurality of holes in a desired pattern. The method also includes positioning the abrading mask in contact with the sound-insulating material and directing a stream of abrasive matter at the abrading mask to create perforations in the sound-insulating material that correspond to the pattern of holes in the abrading mask.

1 . A method for creating acoustic holes in a target material, the method comprising the steps of:
 a) exposing an ultraviolet radiation transparent medium that includes an image of at least a portion of an array of acoustic holes and an ultraviolet sensitive mask with a thickness between approximately 0.002 inches and approximately 0.004 inches to ultraviolet radiation;   b) removing uncured material from the ultraviolet sensitive mask such that cured material forms an abrading mask;   c) positioning the abrading mask in contact with the target material; and   d) directing a stream of abrasive material with a stream pressure between approximately 50 pounds per square inch and approximately 69 pounds per square inch at the abrading mask to create acoustic holes in the target material.   
     
     
         2 . The method of  claim 1 , further including the step of creating the image of at least a portion of the array of holes. 
     
     
         3 . The method of  claim 2 , further including the step of transferring the image to the ultraviolet radiation transparent medium. 
     
     
         4 . The method of  claim 3 , further including the step of positioning the ultraviolet radiation transparent medium in contact with the ultraviolet sensitive mask. 
     
     
         5 . The method of  claim 1 , wherein the target material includes a sound-insulating material for an aircraft engine. 
     
     
         6 . The method of  claim 1 , wherein the abrasive material includes silicon carbide (SiC) particles. 
     
     
         7 . The method of  claim 1 , wherein the abrasive material includes alumina (Al2O3) particles. 
     
     
         8 . The method of  claim 1 , wherein removing uncured material from the ultraviolet sensitive mask includes using a high-pressure liquid rinse. 
     
     
         9 . (canceled) 
     
     
         10 . A method for creating acoustic holes in a sound-insulating material for an aircraft engine, the method comprising the steps of:
 a) creating a positive opaque image of at least a portion of an array of acoustic holes;   b) transferring the image to an ultraviolet radiation transparent medium;   c) positioning the ultraviolet radiation transparent medium in contact with an ultraviolet curable mask with a thickness between approximately 0.002 inches and approximately 0.004 inches;   d) exposing the ultraviolet radiation transparent medium and the ultraviolet curable mask to ultraviolet radiation to cure exposed areas of the mask;   e) removing uncured material from the ultraviolet curable mask using a high-pressure water rinse such that the cured material forms an abrading mask;   f) positioning the abrading mask in contact with the sound-insulating material; and   g) directing a stream of abrasive material with a stream pressure between approximately 50 pounds per square inch and approximately 69 pounds per square inch at the abrading mask to create acoustic holes in the sound-insulating material.   
     
     
         11 . The method of  claim 10 , wherein the abrasive material includes silicon carbide (SiC) particles. 
     
     
         12 . The method of  claim 10 , wherein the abrasive material includes alumina (Al2O3) particles. 
     
     
         13 . A method for creating acoustic holes in a sound-insulating material for an aircraft engine, the method comprising the steps of:
 a) creating a positive opaque image of a portion of an array of acoustic holes;   b) transferring the image to an ultraviolet radiation transparent medium;   c) positioning the ultraviolet radiation transparent medium in contact with an ultraviolet curable mask with a thickness between approximately 0.002 inches and approximately 0.004 inches;   d) exposing the ultraviolet radiation transparent medium and the ultraviolet curable mask to ultraviolet radiation to cure exposed areas of the mask;   e) removing uncured material from the ultraviolet curable mask using a high-pressure water rinse such that the cured material forms an abrading mask;   f) positioning the abrading mask in contact with a first location of the sound-insulating material;   g) directing a stream of abrasive material with a stream pressure between approximately 50 pounds per square inch and approximately 69 pounds per square inch at the abrading mask to create acoustic holes;   h) positioning the abrading mask in contact with a second location of the sound-insulating material and directing a stream of abrasive material at the abrading mask to create acoustic holes; and   i) repeating step h) until acoustic holes have been created at all desired locations of the sound-insulating material.