1、mIL-F-qBb36 bb m 9999906 0337097 6 m L F- /7-%s MIL-F-48616 29 JULY 1977 MILITARY SPECIFICATION FILTER (COATINGS), INFRARED INTERFERENCE : GENERAL SPECIFICATION FOR This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope.- This specific
2、ation establishes general performance and durability requirements for thin film coated optical elements which are used in the spectral region from 0.7 um to 50.0 um (See 6.1). 2. APPLICABLE DOCUMENTS 2.1 The following documents, of the issue in effect on date of invitation for bids or requests for p
3、roposal, form a part of this specification to the extent specified herein. SPECIFICATIONS Federal L-T-90 ccc -c -440 Military MIL-E-12397 MIL-1-45607 STANDARDS MIL-STD-105 MIL-STD-O MIL-STD-1241 Tape, Pressure-Sensitive Adhesive Cellophane and Cloth, Cheesecloth, Cotton Bleached and Unbleached Cellu
4、lose Acetate Eraser, Rubber-Pumice for Testing Coated Optical Inspection Equipment, Acquisition, Maintenance and E lement s Disposition of Sampling Procedure and Tables for Inspection by Quality Assurance Terms and Definitions Optical Terms and Definitions Attributes Beneficial comments (recommendat
5、ions , additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commander, U. S. Army Armament Research a temperature between 6O0F and -t90F (16OC and 32OC). 9 Provided by IHSNot for ResaleNo reproduction or networking permitted without lice
6、nse from IHS-,-,-MIL-F -486 16 4.3.2.3 Acceptance and rejection.- Rejected lots shall be screen- ed for all defective characteristics. Removal of defective units and resubmittal or rejected lots shall be in accordance with “Acceptance and Rejection“ as specified in MIL-STD-105. 4.3.2.4 Special sampl
7、ing.- A minimum of three coated witness pieces, or coated components (when required), shall be selected as samples from each evaporation lot. Each sample shall meet the requirements and tests in Table V. The sequence of test shall be as delineated in Table V. TABLE V - CLASSIFICATION OF DEFECTS NO.
8、CHARACTERISTIC 301. Spectral 3 02. Adhe s ion 303. Surface quality, coating (post humidity) 304. Surface quality, cosmetic (post humidity) 305. Moderate abrasion FG3QULREMENT TEST PROCEDURE 3.2 4.6.3 3.4.2.1.1 4.6.8.1 3.4.2.1.2 4.6.8.2, 4.6.7.1 3.4.2.1.2 4.6.7.3 3.4.2.1.3 4.6.8.3 NOTE: The inspectio
9、n for the Characteristics in Table 111 shall be conducted at a temperature between “60 and -t90F (16% and 32OC). 4.3.2.5 Failure of sample.- Should any one item of a special sampling fail to meet the specified test requirements, acceptance of the represented inspection lot shall be suspended by the
10、Government until necessary corrections have been made by the contractor and the resub- mitted items have been approved. (See 4.3.2.3). 4.4 Inspection equipment.- Except as otherwise provided for by the contract, the contractor shall supply and maintain inspection equipment in accordance with the app
11、licable requirements of MIL-1-45607. 4.4.1 Government furnished inspection equipment.- Where the contract provides for Government furnished test equipment, supply and maintenance of test equipment shall be in accordance with applicable requirements specified in MIL-1-45607. 4.4.2 Contractor furnishe
12、d inspection equipment. 4.4.2.1 Government design.- All inspection equipment specified by drawing number in specifications or SQAP forming a part of the contract shall be supplied by the contractor in accordance with technical data included in the contract. 4.4.2.2 Contractor equipment.- The contrac
13、tor shall supply inspec- tion equipment compatible with the “Test Methods and Procedures specified in 4.6 of this specification. Since tolerance of test equipment is nor- mally considered to be within 10% of the product tolerance for which it 10 Provided by IHSNot for ResaleNo reproduction or networ
14、king permitted without license from IHS-,-,-MIL-F-48616 is intended, this inherent error in the test equipment must be considered as part of the prescribed product tolerance limit. Thus, concept, con- struction, materials, dimensions and tolerances used in the test shall be so selected and controlle
15、d as to insure that the test equipment will reliably indicate acceptability of a product which does not exceed 90% of the prescribed tolerance limit, and permit positive rejection when non- conforming. Construction shall be such as to facilitate routine cali- bration of test equipment. 4.4.2.3 Inspe
16、ction equipment design requirements. 4.4.2.3.1 Spectrophotometric equipment.- The spectrophotometer utilized for spectral measurements of finished components, or witness pieces, shall have an optical system collimated to f/4.0, or a larger “f/-“ number. 4.4.2.3.2 Spectrophotometric measurement accur
17、acies. 4.4.2.3.2.1 Wavelength resolution, scanning speed and time constant.- The wavelength resolution of the spectrophotometer shall be better than that required by the applicable detailed specification sheet. The scan- ning speed and time constant shall be compatible with the resolution require- m
18、ent of the item under test. 4.4.2.3.2.2 Wavelength and photometric accuracy.- When not specified in the applicable detailed specification sheet, the spectral parameters shall be measured to the following accuracies in the region from 0.7 um to 50.0 um : a. Wavelength accuracy. - Plus or minus (t) O.
19、 5% of the wave- length being measured, or in the case of narrow bandpass filters, + 20.0% of the filters half-band width. b. Transmittance (T) accuracy. TRANSMITTING REGION ACCURACY (T 1.0% absolute) f 1.5% of full scale ATTENUATED REGION ACCURACY (T 1.0% absolute) -t 0.1% Q 11 Provided by IHSNot f
20、or ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-48616 c. Reflectance (R) accuracy. HIGH REFLECTANCE REGION ACCURACY (R 80.0%) 2 1.5% of full scale MID -REFLECTANCE REGION ACCURACY (500% R 80.0%) 2 2 .O% of full scale LOW REFLECTANCE REGION (1.5% R 5.0%) (R 1.5%) A
21、CCURACY + 0.1% 5 0.05% 4.5 Inspection documentation. 4.5.1 Spectral.- A copy of the spectral test results shall be supplied with each coating lot and shall contain sufficient data to show compliance with the spectral requirements for the parts being shipped. This data should include as a minimum the
22、 following: a. Type of spectrophotomer used. b. Properly labelled axes with spectral reference lines (e.g. where appropriate, zero reference and/or full scale reference lines). c. Test conditions. d. Actual measured values plus any theoretical or measured corrections to the measured values. 4.5.2 Ph
23、ysical. - Inspection records shall be available which show compliance with all physical requirements. 4.5.3 Environmental.- Inspection records shall be available which show compliance with all environmental durabilify requirements. 4.6 Test methods and procedures. 4.6.1 Cleaning.- Before and after s
24、ubjecting a coated sample (corn- ponent or witness piece) to any inspection or test, the coated sample shall be thoroughly and carefully cleaned to remove dirt, finger marks, smears, etc. The cleaning solution shall be acetone, ethyl alcohol, isopropyl alcohol, or mixtures thereof. Following the cle
25、aning, the coated sample shall be carefully dried with lens tissue or a soft cleanocloth. The temperature of the cleaning solution shall not exceed +80 F (27OC). 12 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-48bLb bb W 77777Ob 0137107 7 I
26、MIL-F-48616 4.6.2 Temperature conditions. - Unless otherwise specified the testing equipment and coated components, or witness pieces, shall be stabilized at a temperature between “60 and + 90F (16OC and 32OC), and maintained at that temperature during all spectral testing. 4.6.3 Spectral.- Perform
27、the test for spectral requirements utilizing the test equipment specified in 4.4.2.3. The measured spectral performance of infrared filters and coatings shall conform to the require- ments of 3.2. unless otherwise specified the measured spectral values for the applicable wavelengths shall be recorde
28、d as measured in vacuum. 4.6.4 Internal defects.- Substrate materials which are transparent, or semi-transparent to visible radiation, shall be visually examined by transmiss ion with the unaided eye for the requirements of 3.3.1. The examination shall be performed using two 15 watt cool white fluor
29、escant light tubes as ehe light source. The viewing distance from the substrate surface to the eye shall not exceed 18.0 inches (45.7 cm), The substrate material shall be viewed against a black matte background. The only illumination in the inspection area shall be from the light source used for exa
30、mination. This method of examination is as depicted in Figure I. The quality of the substrate material shall not exceed the dig tolerance specified in 3.3.1. The method of inspection and the evaluation of transparent and semi-transparent material for internal defects, other than defects which are es
31、sentially round in nature, shall be as specified by the procurement agency. The overall internal quality of the substrate material shall conform to the requirements of 3.3.1. The method of inspection to evaluate the internal quality of substrate materials which do not transmit visible radiation shal
32、l be as specified on the component drawing, or procurement document (See 6.2e). 4.6.5 Substrate surface defects.- The component substrate shall be examined for scratches and digs by reflection or transmission, where applicable using the inspection technique specified in 4.6.4. Magnifi- cation shall
33、be used as needed in these examinations. The length and width of scratches, and the dig diameters shall be determined by use of interferometer, microscopic measuring devices, calibrated precision comparators, or similar applicable precision measuring devices. The width, length and density of all scr
34、atches on the substrate surface shall conform to the requirements of 3.4.1.2 and 3.4.1.2.1. The diameter and density of all digs in the substrate shall conform to the requirements of 3.4.1.3 and 3.4.1.3.1. The quality of each substrate surface shall meet the requirements of 3.3.2. 4.6.6 Substrate di
35、mensions.- The substrate shall be inspected by use of standard measuring equipment (See 6.3.3). The substrate dimensions shall conform to the requirements of 3.3.3. 4.6.7 Surface quality of coated components. 4.6.7.1 Coating.- The coating on the component surface shall be examined for evidence of fl
36、aking, peeling, cracking, etc by reflection or transmission, where applicable, using the inspection technique 13 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-48616 specified in 4.6.4. The coating shall conform to the requirements of 3.4.1.1.
37、 4.6.7.2 Scratch and di acetone; and ethyl alcohol. The immersion time in each solution shall be a minimum of ten minutes. Upon removal from each solution, the solvent shall be allowed to evaporate to dryness without wiping or forced drying before proceeding to the next solution. Upon removal from t
38、he alcohol solution, and after drying any resultant stains on the coated surface shall be removed by wiping the coating to a clean, stain-free condition with an ethyl-alcohol-moistened cheesecloth. Subsequent to this cleaning, the coating shall be subjected to the examinations specified in 4.6.7.1 a
39、nd 15 i -. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-48616 4.6.7.3. The coating shall conform to the requirements of 3.4.2.2.2. 4.6.10 Optional durability tests.- The coated components or witness samples shall withstand exposure to the fo
40、llowing test conditions when specified in the contract, purchase order or on the component drawing (See 6.2j). 4.6.10.1 Severe abrasion.- The coated components, or witness piece, shall be subjected to a severe abrasion by rubbing the coated surface with a standard eraser conforming to MIL-E-12397 mo
41、unted in a eraser abrasion coating tester that conforms to the requirements of Drawing D7680606. The eraser shall be rubbed across the surface of the component, or witness piece, from one point to another over the same path for 10 complete cycles (20 strokes) with a force of 2.0 to 2.5 pounds contin
42、uously applied. The length of the stroke shall be approximately equal to 3 diameters of the eraser when the diameter or area of the component, or witness piece, permits. The eraser abrasion tester shall be held approximately normal to the surface under test during the rubbing operation. Subsequent t
43、o the rubbing operation the component or witness piece, shall be cleaned (See 4.6.1), dried and then subjected to an examination by reflection using the inspection technique specified in 4.6.4 for evidence of physical damage to the coating. The film coating on the component, or witness piece, shall
44、meet the requirements of 3.4.2.3 .l. 4.6.10.2 Salt solubility.- The coated component, witness piece, shall be immersed for a period of 24 hours in a solution of distilled water and sodium chloride (salt). The mixture shall be 6 ounces (170 grams) of salt per gallon (3.8 liters) of water at room temp
45、erature (16 to 32OC). Subsequent to this immersion the coated componGnt, witness piece, shall be removed from the solution and gently washed, or dipped in clean running water not warmer than 100 F (38OC) to remove salt deposits. The coated component, witness piece, shall then be cleaned (See 4.6.1),
46、 dried, and then subjected to the examination specified in 4.6.7.1 and 4.6.7.3. The coated component, or witness piece, shall conform to the requirements of 3.4.2.3.2. 4.6.10.3 Water solubility.- The coated components, or witness piece, shall be immersed for a period of 24 hours in distilled water a
47、t room temperature (-t60F to +90F). Subsequent to this immersion, the coated components, or witness piece, shall be removed from the solution, J cleaned (See 4.6.1), dried, then subjected to the examination specified .in 4.6.7.1 and 4.6.7.3. The coating on the component, or witness piece, shall meet
48、 the requirements of 3.4.2.3.3. 4.6.10.4 Salt spray (fog).- The coated component, witness piece, shall be subjected to a salt spray fog test in accordance with ASTMB-117- 73, for a continuous period of 24 hours. Subsequent to the salt spray fog exposure the coated component, or witness piece, shall
49、be washed and dried as specified. The coated component or witness piece I shall then be cleaned (See 4.6.1), dried, and then subjected to the examination specified in 4.6.7.1. Subsequent to the visual examination for physical defects 16 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-48616 the coated component or witness piece, shall be subjected to the test in 4.6.8.3 or 4.6
