1、MIL-B-50772 12 9997706 O330809 b M MIGB-507 72(MU) 24 March 1972 MILITARY SPECIFICATION BONDING OF PRECISION MIRRORS (Glas s- to-Me tal) 1. SCOPE 1.1 This specification covers the bonding (glass-to-metal) of high re- solution optical mirrors (front surface) to their metal mounts for use in precision
2、 military fire control instruments . 2. APPLLCABLE DOCUMENTS 2,l The following documents, of the issue in effect on date of invita- tion for bids or request for proposal, form a part of this specification to the extent specified herein. SPECIFICATIONS Federal GP-504 Military MIGS-11031 MIGF-139 26 P
3、lastic Sheet and Film, Cellulose Acetate Sealing Compound, Adhesive: Curing (Poly-Sulfide Base) Fire Control Materiel, General Specifi- cation Governing the Manufacture and Inspection of STANDARDS Military MIGSTD-810 Environmental Test Methods (Copies of specifications, standards and drawings requir
4、ed by suppliers in connection with procurement functions should be obtained from the procuring activity or as directed by the contracting officer.) 3. BEQUIREMENTS 3. 1 Assembly Components. 3.1.1 Ootical.- The mirror shall comply with Le requirements for reso- lution, astigmatism, parallelism, etc,
5、specified on the applicable drawing. FSC 12GP I I f. I l. r 4 Licensed by Information Handling Services3.1.2 Metal,- The mirror mount shall comply with the requirements specified on the applicable drawing. 3.1.3 Adhesivec- Bonding materials shall be in accordance with MIL- Sb11031. . 3.1.4 SDacers.-
6、 Spacers used to control bonding thickness shall be 1/4“ -hy L.1125“ i 0.002 thick cellulose acetate in accordance with L-P-504. 3.2 Bondi- Process.- Unless otherwise specified by the procuring agency, assemblies shall be bonded in accordance with the procedure specified herein. Deviation from this
7、procedure is prohibited unless approval is ob- tained from the contracting officer prior to use in production. 3.2.1.1 Mirror .- Polishing compounds , pencil marks and other contaminants shall be removed from the surface of the glass to be bonded by acouring with a past of pumice or calcium carbonat
8、e and water applied with cotton swab. shall be removed by rinsing with distilled water and wiping with clean, dry cheesecloth followed by an ethyl alcohol rinse and wiping. Residue 3,2.1,2 Biefal Component,- The bonding surface shall be of a virgin metal free from corrosion producta, burrs, passivat
9、ion or oxide treatments and any other surface contaminants; such imperfections shall be removed by care- fully rubbing with 1-G emery polishing paper while at the same time not de- stroying the physical dimensions and flatness of the bonding surface, surface shall be wiped with ethyl alcohol saturat
10、ed cheesecloth and allowed to The drp* CATION: Clean surfaces are essential prerequisites for obtaining a eatisf actory bond. 3.2.2 Bond Configuration.- The bond shall take the form of three distinct circlets formed at the comers of an imaginary triangle located as shmn on the applicable assembly dr
11、awing. 3.2,3 Bondinn Fixture.- The botiding fixture shall be designed to pro- vide mechanical positioning of components to be bonded to an accuracy compatible with the applicable drawing and to mdntain a uniform preesure by spring loading. Sufficient support shall be provided to protect components b
12、eing bonded from unnecessary strain. warhour straining or bending. &-the ahslves are influenced by heat during the curing cycle, care shall b-eacerciee- to fabricate fixtures from materials which will maintain align- stint amid pressures. It shall accommodate easy removal of the bonded assembly Sinc
13、e the fixture, optical and metal components 2 Licensed by Information Handling ServicesMIL-B-50772 32 = 777470b 0330833 4 = MIL-B-507 72(MU) 3.2.4 Bonding.- Bonding shall conform to the procedures outlined be- These techniques involve the basic operations of bonding with a poly- low. sulfide adhesiv
14、e/sealant whose mix ration is modified for this specific application. 3.2.4.1 Adhesive Mix Ratio.- Mix the adhesive of MIGS-11031 in the ratio of two parts base to one part accelerator. insure complete dispersion of the accelerator in the base, Do not mix more material than is necessary to bond 2 or
15、 3 assemblies at one time as the pot life of the adhesive at this mix ratio is short. Stir thoroughly so as to 3.2.4.2 Adhesive Application.- Place the mirror in the fixture with the surface to be bonded facing up. “Puddle“ the adhesive on the three distinct areas of the glass surface at the locatio
16、ns specified on the applicable drawing. A sufficient, but not excessive, quantity of adhesive should be deposited such that when the metal support bracket is placed in position, three separate circlets approximately 1“ to 1-1/8“ in diameter by 0.025 thick will be formed. CAUTION: The circlets shall
17、not touch one another after cure. 3.2.4.3 Spacing.- Within each puddle of adhesive centrally place the 0.025“ thick spacer and press it down through the adhesive until it bottoms on the glass surface. 3.2.4.4 Metal Component Positioning and Application of Pressure.- Care- fully locate the metal comp
18、onent on the adhesive puddles in the proper position as shown on the applicable drawing. back of the component so that the adhesive flows out to a maximum of 1-1/8“ diameter circle and the metal component bottoms on the spacers to yield a bond thickness of 0.025“. oven cure, Slowly and evenly apply
19、pressure to the Maintain a 5 psi pressure on the assembly during the 3.2.4.5 Cure.- unheated circulating air-type oven, and raise the temperature to a curing level of 160 f 5F. fixture from oven and allow the bonded assembly to cool to rom temperature. Assure that both the mirror and metal component
20、 are securely fastened and undisturbed during cure so that the assembly will meet the requirements speci- fied on the applicable drawing. Place the fixture holding the prepared assembly in an Maintain this taperature for a minimum of 4 hours. Remove NOTE: In sme cases it is possible to remove the bo
21、nded assembly from the fixture immediately after the oven cure without affecting any optical or mechanical properties. 3.3 Performance Requirements.- The bonded assembly shall meet the align- ment and optical performance requirements as specified on the applicable draw- ing after the following envir
22、onmental conditions : :, I 3 Licensed by Information Handling ServicesMIL-B-50772 12 7797906 0330812 b . 3.3.1 Elevated Temperature Thermal Stability.- After stabilization at roan temperature, exposure at 160 2 2F for 4 hours. 3.3.2 Low Temperature Thermal Stability.- After stabilization at room tem
23、perature, exposure at -80“ & 2F for 4 hours. 3.3.3 Mechanical Shock.- Subsequent to 3.3.1 and 3.3.2, 200 g applied The shock pulse shall have parallel to the bonded surface, repeated 3 times. a wave form approximately a half-sine wave with a minimum time duration of 2 2 0.5 milliseconds. 3.4 Workman
24、ship.- Workmanship shall be of the highest quality consis- tent with the requirements of this specification. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection.- Unless otherwise specified in the contract or purchase order, the supplier is responsible for the performance of all inspec
25、tion requirements as specified herein. fied, the supplier may utilize his own facilities or any commercial laboratory acceptable to the Government. any of the inspections set forth in the specification where such inspections are deemed necessary to assure supplies and services conform to prescribed
26、requirements . 4.2 Performance Requirements.- Each bonded assembly shall meet the requir-ents specified in 3.3 utilizing the test methods specified herein. Bonded assemblies shall be prepared in accordance with Section 3, and deviations therefrom shall not be permitted without prior approval of the
27、contracting officer Except as otherwise speci- The Government reserves the right to perfom 4.2.1 Elevated Temperature.- Thermal Stability - The bonded assembly shall be subjected to the requirement specified in 3.3.1. The testing equip- ment utilized for this test shall be in accordance with the “Te
28、st Facilities of MIGF-13926. when the assembly is inserted. raised gradually to +160F (see Note). temperature for a minimum of 4 hours. the temperature of the test chamber shall be gradually reduced to room tem- perature. Subjected to the test specified in 4.2.2, The test chamber shall be at room te
29、mperature-(+6Oo to +90“F) The temperature of the test chamber shall be The assembly shall remain at this At the completion of this 4 hour period The bonded assembly shall be removed frm the test chamber and NOTE: The rate of temperature change in the test chamber shall not . exceed 20 degrees per ho
30、ur throughout the temperature cycling operation of %he tests in 4.2,l and 4.2.2, :?e. 4.2.2 Low Temperature Thermal Stability.- The bonded assembly shall The testing equipment The test Regu- be subjected to the requirements specified in 3.3.2. utilized in this test shall conform to the requirements
31、of 4.2.1. chamber shall be at room temperature when the assembly is inserted. late the temperature of the test chamber to OF. permitted to stabilize at this temperature. The assembly shall be The temperature of the chamber 4 Licensed by Information Handling ServicesMIL-B-50772 L2 7999906 0330833 8 -
32、 _ MIL-B- 50 7 72 (MU) shall then be reduced gradually to -80OF. this temperature for a minimum of 4 hours. hour period the temperature of the test chamber shall be gradually raised to rom temperature. room temperature it shall be removed from the test chamber and subjected to the test specified in
33、4.2.3. The assembly shall remain at At the completion of this 4 . When the bonded assembly has been stabilized at 4.2.3 Mechanical Shock.- The bonded assembly shall be shock tested in accordance with Procedure IV, Method 516.1 of MIL-STD-810, except that the direction and number of shocks shall be a
34、s specified in 3.3.3. pulse shape, peak valve and time duration shall be in accordance with 3.3.3. The adapter utilized for mounting the bonded assembly on the shock machine shall securely hold the pivot axis in a vertical plane within 2 degrees. Upon Completion of the specified shock impulses the g
35、lass and metal com- ponents of the assembly shall be examined for evidence of physical daaage. Any evidence of damage shall be cause for rejection of the bonded assembly. Subsequent to the shock test the bonded assembly shall meet the performance requirements of 3.3. 5. PREPARATION FOR DELIVERY The
36、slock 5.1 Packaging, packing and marking are not applicable to the specifica- tion. 6. NOTES 6.1 Intended Use.- Bonded mirror assemblies covered by this specifica- tion are primarily intended for those applications where minimal dis tortion of the mirror by the adhesive bond is required. for assembl
37、ies requiring an optical resolution better than 2 seconds of arc. This bonding method may find application for elliptical reflectors and beam splitters but should be thoroughly tested prior to use. As such, it is normally used 6.2 Ordering Data.- Procurement documents should specify the title, number, and date of this specification. Custodian: Army-Mu Preparing Activity: Amy - MU Pro j ect No. 12GP-AO32Y * U. L GOVERNMENT PRINTIN WFiCLr 1972 -714-164/6436 5 Licensed by Information Handling Services
