1、6 -92 -% MIL-S-230C 12 January 1983 SUPERSEDING MIL-S-230B 7 August 1969 MILITARY SPE C IF ICATI ON SILICON, POWDERED, TECHNICAL This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers two grades and four clas
2、ses of technical grade powdered silicon. 1.2 Classification. Silicon shall be of the following grades and classes as specified (see 6.2): Grade I Class A Class B Class D Grade II Class C 2. APPLICABLE DOCUMENTS 2.1 Government documents. 2.1.1 Specifications, standards, and handbooks. Unless otherwis
3、e specified, the following specifications, standards, and handbooks of the issue listed in that issue of the Department of Defense Index of Specifications and Standards (DoDISS) specified in the solicitation form a part of this specification to the extent specified herein. : Beneficial comments (rec
4、ommendations, additions, deletions) and any perti- : : nent data which may be of use in improving this document should be addressed: : to: Commander, US Army Armament Research and Development Command, ATTN: : DRDAR-TSC-S, Aberdeen Proving Ground, MD 21010 by using the self-addressed : : Standardizat
5、ion Document Improvement Proposal (DD Form 1426) appearing at : : the end of this document or by letter. FSC 6810 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-S-230C 68 777770b 0113582 4 MIL-S-230C SPECIFICATIONS FEDERAL RR-S-366 - Sieve Test
6、 STANDARDS MILITARY MIL-STD-105 - Sampling Procedures and Tables for Inspection by Attributes 2.1.2 Other Government documents, drawings, and publications. The following other Government documents, drawings, and publications form a part of this specification to the extent specified herein. CODE OF F
7、EDERAL REGULATIONS (CFR) 49 CFR 171 to 179 - Department of Transportation Hazardous Materials Regulations (The Code of Federal Regulations is available from the Superintendent of Docu- ments, US Government Printing Office, Washington, DC 20402. Orders for the above publication should cite “49 CFR 17
8、1 to 179.“) (Copies of specifications, standards, handbooks, drawings, and publications required by manufacturers in connection with specific acquisition functions should be obtained from the contracting activity or as directed by the contract- ing officer . ) 2.2 Other publications. The following d
9、ocuments form a part of this speci- fication to the extent specified herein. The issues of the documents which are indicated as DoD adopted shall be the issue listed in the current DoDISS and the supplement thereto, if applicable. ASTM STANDARDS D1193 - Reagent Water (Application for copies should b
10、e addressed to ASTM, 1916 Race Street, Philadelphia, PA 19103.) (Industry association specifications and standards are generally available for reference from libraries. They are also distributed among technical groups and using Federal agencies.) 2.3 Order of precedence. In the event of a conflict b
11、etween the text of this specification and the references cited herein, the text of this Specifica- tion shall take precedence. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-S-230C b8 m 7777706 OLL3583 6 m MIL-S-230C 3. REQUIREMENTS 3.1 Chemic
12、al characteristics. Silicon shall conform to the applicable chemical characteristics of table I when tested as specified therein. TABLE I. Chemical characteristics : Grade I : Grade II : Test Characteristic . paragraph : : Silicon, minimum percent by weight : 97.0 : 96.5 : 4.2.4.1 : : Iron, maximum
13、percent by weight : 1.00 : - : 4.2.4.2(a): : Aiuminum, maximum percent by weight : 1.00 : - : 4.2.4.2(b): 3.2 Granulation characteristics. Silicon shall conform to the applicable granulation characteristics of table II when tested as specified in 4.2.4.3. TABLE II. Granulation characteristics Percen
14、t by weight passing : Class A : Class B : Class C : Class D : Sieve size : 99.0 : : No. 170, minimum : - : - : 98.0 : - : : No. 100, minimum : 99.0 : - . - : No. 200, minimum : 80.0 : 99.9 : - . - : No. 230, minimum : - : - : 90.0 : - : : No. 230, maximum : - : - : - : 50.0 : 4. QUALITY ASSURANCE PR
15、OVISIONS 4.1 Responsibility for inspection. Unless otherwise specified in the con- tract or purchase order, the contractor is responsible for the performance of all inspection requirements as specified herein. in the contract or purchase order, the contractor may use his own or any other facilities
16、suitable for the performance of the inspection requirements speci- fied herein, unless disapproved by the Government. The Government reserves the right to.perform any of the inspections set forth in the specification where such inspections are deemed necessary to assure supplies and services conform
17、 to prescribed requirements. Except as otherwise specified 4.2 Quality conformance inspection. 4.2.1 Lotting. A lot shall consist of the silicon of one grade and class produced by one manufacturer, at one plant, from the same materials, and under essentially the same manufacturing conditions provide
18、d the operation is con- tinuous. In the event the process is a batch operation, each batch shall con- stitute a lot (see 6.3). 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-S-230C 68 7999906 OLL358Li 8 MIL-S-230C 4.2.2 Sampling. 4.2.2.1 For
19、examination of packaging. Sampling shall be conducted in accord- ance with MIL-STD-105. 4.2.2.2 For silicon test. Sampling shall be conducted in accordance with table III. A representative specimen of approximately 500 grams (g) shall be removed from each sample container and placed in a suitable cl
20、ean, dry con- tainer labeled to identify the lot and container from which it was taken. TABLE III. SamDline: for silicon test : Number of containers in batch or lot : Number of sample containers : 3 to 150 151 to 1,200 1,201 to 7,000 7,001 to 20,000 Over 20,000 3 5 8 10 20 4.2.2.3 For container leak
21、age test. Sampling shall be conducted in accord- ance with MIL-STD-105. 4.2.3 Inspection procedure. 4.2.3.1 For examination of packaging. The sample unit shall be one filled container, ready for shipment. Sample containers shall be examined for the following defects using an AQL of 2.5 percent defec
22、tive: (a) Contents per container not as specified (b) Container not as specified (c) Container damaged or leaking (d) Marking incorrect, missing, or illegible 4.2.3.2 For silicon test. Each sample specimen taken in 4.2.2.2 shall be tested as specified in 4.2.4. cause for rejection of the lot represe
23、nted. Failure of any test by any specimen shall be 4.2.3.3 For container.1eakage test. The sample unit shall be one container. The sample containers selected in 4.2.2.3 shall be tested as specified in 4.2.5 using an AQL of 1.5 percent defective. 4.2.4 Silicon tests. Water in accordance with ASTM D11
24、93, type as appli- cable, and reagent grade chemicals shall be used throughout the tests. applicable, blank determinations shall be run and corrections applied where significant. Tests shall be conducted as follows: Where 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without
25、 license from IHS-,-,- MIL-S-230C b W 7q777Ob OLL355 T MIL-S-230C 4.2.4.1 Silicon. Prepare a fusion mixture by grinding 10 g of anhydrous sodium carbonate and 1 g of potassium nitrate to a fine powder. Place 3 to 4 g of this mixture in a platinum crucible having a 35 to 50 milliliter (mL) capac- ity
26、. 0.5 g of the specimen. Cover the specimen with all but approximately 1 g of the fusion mixture. Thoroughly mix the fusion mixture and specimen by stirring with a vertically held platinum rod moving in a circular path. Care must be taken to keep a layer of fusion mixture that is free from silicon o
27、n the bottom of the crucible to prevent alloying of silicon with the platinum at high temper- atures. to the rod into the crucible. Add the remaining portion of the fusion mixture, distributing it evenly to form a cover which will help prevent spattering. Place the uncovered crucible on a silica tri
28、angle and apply a small flame of a bunsen burner to the outside of the crucible above the surface of the mixture. Carefully heat the upper half .of the crucible for about 20 minutes. forms on the surface and it pulls away from the side, heat the lower half of the crucible on the sides, taking care n
29、ot to get it too hot or the reaction will become violent and spatter. Cover the crucible to prevent loss of con- tents if the reaction becomes violent. After heating the main portion of the mixture with the bunsen burner for 30 minutes, use a blast burner to continue the heating. When the mixture ha
30、s been well sintered and there is no evidence of continued reaction, increase the heat on the bottom of the crucible slowly to prevent loss of contents due to liberation of carbon dioxide from the pasty mass. Fusion is completed when all of the mixture has been reduced to a clear liquid containing n
31、o undissolved particles. Continue heating the liquid for an additional 5 minutes to insure complete reaction. Fuse any material adhering to the lid by heating. The total fusion time is 1.5 to 2 hours. Grasp the crucible with platinum-tipped tongs and rotate it to spread the liquid mass on the sides.
32、 This will hasten solution of the mass when it is reacted with hydro- chloric acid. Allow the crucible to cool. Place the crucible and lid into a 750-mL porcelain casserole and cautiouslyadd 200 mL of 22-percent hydrochloric acid. Cover with a watchglass supported by a glass triangle and place on a
33、steam bath. When effervescence ceases, remove the crucible and lid and wash any material adhering to them into the casserole with the minimum amount of water necessary. Carefully evaporate the solution to dryness. Add 10 mL of concentrated hydrochloric acid to the residue, mix thoroughly, and then a
34、dd 100 mL of hot water. Heat and stir until all soluble salts are dissolved. Filter the solution through Whatman No. 40 filter paper and wash the residue at least three times with hot water (this residue is designated as residue I). the filtrate and washings to the casserole, evaporate to dryness on
35、 a steam bath, and heat in an oven for 1 hour at 150 + 2OC. Cool, add 10 mL of con- centrated hydrochloric acid and 100 mL of hot-water and stir thoroughly. the solution, filter, and wash the residue with hot water (this residue is designated as residue 11). determination of iron and aluminum in 4.2
36、.4.2. During the second evaporation, transfer residue I and filter paper to the same crucible used for the fusion. Place the crucible in a cold muffle furnace with the lid removed and slowly heat to 120OOC in approximately 1-1/2 hours. Keep the crucible at 1200C for another 30 minutes. Cover the cru
37、cible, cool to room temperature in a desic- cator and weigh to the nearest 0.1 mg. Using a Meker burner, and keeping the Weigh into the crucible to the nearest 0.1 milligram (mg) approximately When the mixture appears uniformly gray, brush any material adhering As a crust Return Heat Save the combin
38、ed filtrate and washings for the 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-S-230C lid on the crucible, repeat the heating, cooling, and weighing until a constant temperature is obtained. Moisten the residue with a few drops of 1 to 1 sul-
39、 furic acid and 2 to 3 mL of water. Add hydrofluoric acid carefully until the cruible is approximately half full. should be performed in a well-ventilated hood.) dryness on a hotplate. to constant weight. dioxide. Treat residue II in the same manner as residue I. The combined losses in weight from b
40、oth volatilizations represents the total amount of silicon dioxide. Calculate the percent by weight silicon as follows: (All operations using hydrofluoric acid Evaporate the solution to The loss in weight of the crucible represents silicon Ignite the crucible in a Meker flame, cool, and weigh 46.74
41、(A + B) W Percent by weight silicon = where: A = Loss in weight in residue I volatilization in grams, B = Loss in weight in residue II volatilization in grams, and W = Weight of specimen in grams. 4.2.4.2 Iron and aluminum. Fuse residue I and residue II (see 4.2.4.1) with a small amount of potassium
42、 persulfate. Dissolve the fused mass with concen- trated hydrochloric acid and add the resulting solution to the combined fil- trate and washings reserved from the same silicon determination in 4.2.4.1. Heat the solution to 80“ to 90C and saturate thoroughly with hydrogen sulfide. water which has be
43、en saturated with hydrogen sulfide and acidified with 1 to 20 sulfuric acid. Boil the solution until all of the hydrogen sulfide has been expelled and then oxidize the iron by the addition of bromine water until the solution becomes distinctly yellow. Boil the solution until all of the bromine has b
44、een expelled and adjust the volume of the solution to approximately 150 mL with water. Add a 1 to 1 solution of ammonium hydroxide until the solution is alkaline to methyl red, then add 2 or 3 mL in excess. Allow to digest for 10 to 15 minutes, fil- ter, and wash several times with hot l-percent amm
45、onium nitrate solution, dis- carding the filtrate and washings. Dissolve the precipitate on the filter paper with hot 1 to 1 hydrochloric acid and wash the paper thoroughly with hot water. Using the above procedure, reprecipitate the iron and aluminum and fil- ter through a Whatman No. 41 filter pap
46、er. Wash with hot l-percent ammonium nitrate solution. Place the filter paper and precipitate in a platinum cruc- ible which has been ignited to constant weight at 800“ + 50C. Ignite gently until the paper is charred, and then ignite to constant-weight in a muffle fur- nace at 800 + 10C. Cool to roo
47、m temperature in a desiccator and weigh to the nearest 0.1 mg. The weight of the iron and aluminum oxide precipitates is used in the calculation for percent aluminum. Let the solution stand for approximately 30 minutes, filter, and wash with _- Add three or four drops of methyl red indicator solutio
48、n. (a) Iron. Fuse the residue in the crucible from 4.2.4.2 with 5 to 10 g of potassium bisulfate. heating with 100 mL of water containing 5 mL of 1 to 1 sulfuric acid in a beaker. Remove the crucible and wash thoroughly with hot water, adding the washings to the beaker. Pass hydrogen sulfide gas thr
49、ough the solution for Allow to cool, and dissolve the cooled melt by 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-S-230C approximately 30 minutes. the precipitate with water saturated with hydrogen sulfide and acidified with 1 to 20 sulfuric acid. Catch the filtrate and washings in the same beaker, boil vigorously for 30 minutes to remove the hydrogen sulfide, cool
