ARMY TM 5-6115-612-34 NAVY A-320B0-MME-000 f Approval        To    ensure    adequate    performance characteristics,   parts   sprayed   in   accordance   with   this specification   shall   be   approved   by   Quality   Assurance, unless such approval Is waived g Rejections  Parts  on  which  the  sprayed  coating does not conform to the requirements of this specification,   or   to   authorized   modifications,   shall   be subject to rejection. h.   Approved Equipment and Materials The following equipment and materials are approved for  use under requirements of this specification (1) Equipment Metco gun (2) Wire coating alloys (a) SF aluminum (item 20, appx B) (b) AVCO     silicon     aluminum     (item     16, appx B) (3) Silicone resin alloys (a) Silicone Resin (Item 18, appx B) (b) Silicone Resin (item 17, appx B) (c) Silicone Resin (Item 19, appx B) D7.   Flame     Spray     Coating     -     Aluminum     Bronze, Silicone Resin Impregnated. a Scope (1) Type This specification covers the procedure  for   flame   spray   deposition   of   an   aluminum bronze   coating   and   the   impregnation   of   the   sprayed coating with a silicone resin (2) Application  Primarily    to    provide  abrasion, wear, and corrosion resistant surfaces on aluminum and magnesium alloy parts b.   Applicable     Documents     The     latest     issue     of Aerospace Material Specifications (AMS) shall apply. (1) Engineering Material Specifications • Aluminum  bronze  wire  (item  20,  appx B) • Nickel-aluminum  composite  (item  11, appx B) (2) Engineering Process Specifications • Vapor degreasing (Item 4, appx B) • Grit blasting (item 3, appx B) • Solvent, petroleum (item 5, appx B) c Requirements (1) Equipment An approved metalzing equipment designed to provide automatic gas pres- sure and wirer feed control (2) Coating materials (a) Bond coat (item 11, appx B) (b) Coating alloy (item 20, appx B) (c) Resin sealer coat (item 15, appx B) d Procedure WARNING Toxic solvent is used for general cleaning Illness or skin    damage    may    be    caused    by    prolonged breathing    of    solvent    fumes    or    excessive    skin contact  with  the  liquid  Ensure  there  is  adequate ventilation  and  avoid  open  flame  or  sparks  when using flammable solvent (1) Cleaning.  Parts shall be thoroughly cleaned free  from  grease,  oil,  dirt,  or  other  foreign  materials  by vapor  degreasing  or  by  washing  in  petroleum  solvent (Item 5, appx B) or other suitable solvent (2) Masking Parts shall be masked as required to protect areas not designated to be coated Masks may be   steel,   brass,   or   other   suitable   materials   properly protected against adherence of the sprayed coating (3) Surface conditioning. Grit blast the masked parts sufficiently to remove all metallic luster, excessive blasting snail be avoided (a) Care     must     be     taken     to     prevent contamination  of  the  prepared  surfaces  by  contact  or other  means  If  necessary  to  handle  the  prepared  part, clean,  lint-free  gloves  (item  6,  appx  B)  must  be  used Parts shall be spray coated as soon as possible, but In no  case  longer  than  2  hours  after  surfaces  have  been prepared for coating If this time is exceeded, repeat step (3). (b) Wipe  grit  blasted  surfaces  with  clean, lint-free  rag  (Item  7,  appx  B)  dampened  with  acetone (Item  1,  appx  B)  or  other  suitable  solvent  just  prior  to spraying 14-8    Change 4