1、 INCH-POUND MIL-PRF-46194A8 August 1997SUPERSEDINGMIL-F-4619418 July 1988PERFORMANCE SPECIFICATIONFOAM, RIGID, STRUCTURAL, CLOSED CELLThis specification is approved for use by all Departments and Agencies of theDepartment of Defense.1. SCOPE1.1 Scope . This specification covers rigid, structural, cl
2、osed cellfoam (see 6.1).1.2 Classification . The foam to be of the following types and classes:Type I For processing up to temperatures of 250 o F (121 o C)Class 1 2.0 lb m /ft 3 (32.0 kg/m 3 ) density, nominalClass 2 3.2 lb m /ft 3 (51.3 kg/m 3 ) density, nominalClass 3 4.7 lb m /ft 3 (75.3 kg/m 3
3、) density, nominalType II For processing up to temperatures of 350 o F (177 o C) afterpost-curing (see 6.4)Class 2 3.2 lb m /ft 3 (51.3 kg/m 3 ) density, nominalClass 3 4.7 lb m /ft 3 (75.3 kg/m 3 ) density, nominalClass 4 6.9 lb m /ft 3 (110.5 kg/m 3 ) density, nominalClass 5 12.8 lb m /ft 3 (205.0
4、 kg/m 3 ) density, nominalClass 6 18.7 lb m /ft 3 (299.5 kg/m 3 ) density, nominal2. APPLICABLE DOCUMENTS2.1 General . The documents listed in this section are specified in sections 3and 4 of this specification. This section does not include documents in othersections of this specification or recomm
5、ended for additional information or asexamples. While every effort has been made to ensure the completeness of thislist, document users are cautioned that they must meet all specifiedrequirements documents cited in sections 3 and 4 of this specification,whether or not they are listed. Beneficial com
6、ments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Director, U.S. Army Research Laboratory, Weapons and Materials Research Directorate, ATTN: AMSRL-WM-M, APG, MD 21005-5069 by using the Standardization Document
7、Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. AMSC N/A AREA CMPSProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2MIL-PRF-46194A2.2 Non-Government publications . The following documents form a part of thisdocu
8、ment to the extent specified herein. Unless otherwise specified, theissues of the documents which are DoD adopted are those listed in the issue ofthe DoDISS cited in the solicitation. Unless otherwise specified, the issuesof documents not listed in the DoDISS are the issues of the documents cited in
9、the solicitation (see 6.2).AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM)ASTM C273 - Standard Test Method for Shear Properties ofSandwich Core MaterialsASTM D638/ - Standard Test Method for Tensile Properties ofD638M PlasticsASTM D910 - Standard Specification for Aviation GasolinesASTM D1621 - St
10、andard Test Method for Compressive Properties ofRigid Cellular PlasticsASTM D1622 - Standard Test Method for Apparent Density of RigidCellular Plastics(Application for copies should be addressed to the American Society forTesting and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428).SOC
11、IETY OF AUTOMOTIVE ENGINEERS (SAE)AS 1241 - Fire Resistant Phosphate Ester Hydraulic Fluid forAircraft(Application for copies should be addressed to Aerospace MaterialSpecifications, 400 Commonwealth Drive, Warrendale, PA 15096).2.3 Order of precedence . In the event of a conflict between the text o
12、f thisdocument and the references cited herein, the text of this document takesprecedence. Nothing in this document, however, supersedes applicable laws andregulations unless a specific exemption has been obtained.3. REQUIREMENTS3.1 First article . When specified in the contract or purchase order, a
13、 sampleshall be subjected to first article inspection (see 4.2.1).3.2 Recycled, recovered, or environmentally preferable materials . Recycled,recovered, or environmentally preferable materials should be used to themaximum extent possible provided the material meets or exceeds all specifiedrequiremen
14、ts and promotes economically advantageous life cycle costs.3.3 Material . The material shall be a dimensionally stable, closed cell,rigid foam. The foam material shall be homogeneous throughout. The cells shallbe of approximately the same size, without large accumulations of unexpandedresin, or othe
15、r inclusions. The foam shall be free of cracks, surfaceirregularities, handling damage, and contaminants. The foam shall conform tothe dimensional requirements of the purchase order.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3MIL-PRF-46194A3.4 T
16、hermal stability . Type I expanded foam shall maintain dimensionalstability at temperatures up to 250 o F (121 oC). Type II foam shall maintaindimensional stability at temperatures up to 350 o F (177 o C).3.5 Marking . Each individual sheet shall be permanently marked in one cornerwith the following
17、 information:a) Material specifi cation number, revision letterb) Type and classc) Lot number and batch numberd) Date of manufacturee) Manufacturers product designation3.6 Properties . Unless otherwise specified, the physical, chemical, andmechanical properties of the foam shall be as specified here
18、in when tested inaccordance with the test methods listed in Table V.3.7 Physical properties . The density range and maximal water absorption ofthe foam shall be as specified in Table I.3.8 Fluid resistance . The foam shall be resistant to the fluids listed inTable II. The compressive strength of the
19、 foam at 73.4 + 3.6 o F (23.0 + 2.0 o C)shall remain above the minimal values specified in 3.3.3 when immersed in thefluids for the exposure times and temperatures as specified in Table II.3.9 Mechanical properties .3.9.1 Type I foam . The minimal mechanical properties of type I foam shall beas spec
20、ified in Table III.3.9.2 Type II foam . The minimal mechanical properties of type II foam shallbe as specified in Table IV.4. VERIFICATION4.1 Verification alternatives . Alternative test methods, techniques, orequipment, including the application of statistical process control, toolcontrol, or cost
21、effective sampling procedures may be proposed by thecontractor. Acceptable alternative verification approaches shall be identifiedin the contract.4.2 Classification of inspection . The examination and testing of the foammaterial shall be classified as follows:a) First article inspection (see 4.2.1)b
22、) Conformance inspe ction (see 4.2.2)4.2.1 First article inspection . First article inspection shall be performedon the first production-representative samples of an order when a firstarticle sample is required (see 3.1). The first article sample(s) shall beexamined for all the provisions specified
23、by the procuring activity, thecontract or the purchase order (see 6.2). This inspection shall consist of thetests specified in table V.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4MIL-PRF-46194A4.2.2 Conformance inspection . Conformance inspectio
24、n for acceptance of rigid,structural, closed cell foam shall meet all the provisions specified by theprocuring activity, the contract or the purchase order (see 6.2).4.3 Lot size . Lot size shall consist of all foam material of the same densityproduced from one batch during a single production run.4
25、.4 Sampling . Unless otherwise specified, at least one sample sheet which isrepresentative of each lot (4.3) shall be selected at random for conformancetesting. When material is supplied in thicknesses of less than 1 inch (2.5cm), the supplier shall also furnish material from the same lot, not less
26、than1 inch (2.5 cm) thick for conformance inspection.4.5 Water absorption test . Water absorption shall be determined on fivespecimens selected at random from each density submitted for testing. Eachspecimen shall be 2 inches by 2 inches by 1 inch thick (5 x 5 x 2.5 cm). Thespecimens shall not be se
27、aled or protected with any coating which wouldinhibit moisture absorption. After drying as specified in 6.3, the specimensshall be allowed to cool to room temperature (73.4 + 3.6 o F) (23.0 + 2.0 o C) inan environmentally controlled (50 + 5% RH) room for 2 hours, and then shall beweighed. The specim
28、ens shall then be placed into an environmental chamber at arelative humidity of 85 + 2 percent and a temperature of 160 + 5 o F (71 + 3 o C).Specimens shall be removed from the chamber periodically (but at least once aweek), allowed to cool to room temperature, then reweighed to determine weightafte
29、r exposure. The above procedure shall be repeated until the equilibriummoisture level (saturation) is attained. Equilibrium shall be defined as twoconsecutive weekly measurements indicating a moisture gain of less than 0.05percent. Except for reweighing, wet conditioning shall not be interrupted.Cal
30、culate moisture absorption for each specimen as: weight (percent) absorbed= (weight wet specimen - weight dry specimen)/(weight dry specimen) x 100. Calculate the average moisture absorbed.4.6 Noncompliance .4.6.1 Rejection . Unless otherwise specified where one or more test specimensfail to meet th
31、e requirements of the specification, the lot represented by thespecimen or specimens shall be subject to rejection.4.6.2 Retest . When a sampling plan is not provided or approved by theprocuring agency, where there is evidence that indicates that the specimen wasnot representative of the lot of mate
32、rial, and when the contract does nototherwise specify, at least two specimens shall be selected to replace eachtest specimen which failed. All specimens so selected for retest shall meetthe requirements of the specification or the lot shall be subject torejection.4.7 Test results . Test results shal
33、l be kept in the contractors file for theduration of the contract.5. PACKAGING5.1 Packaging . For acquisition purposes, the packaging requirements shall beas specified in the contract or order (see 6.2). When actual packaging ofProvided by IHSNot for ResaleNo reproduction or networking permitted wit
34、hout license from IHS-,-,-5MIL-PRF-46194Amateriel is to be performed by DoD personnel, these personnel need to contactthe responsible packaging activity to ascertain requisite packagingrequirements. Packaging requirements are maintained by the Inventory ControlPoints packaging activity within the Mi
35、litary Department or Defense Agency,or within the Military Departments System Command. Packaging data retrievalis available from the managing Military Departments or Defense Agencysautomated packaging files, CD-ROM products, or by contacting the responsiblepackaging activity.6. NOTES(This section co
36、ntains information of a general or explanatory nature whichmay be helpful, but is not mandatory).6.1 Intended use . The foams which are specified in this document are rigid,closed cell materials comparable in density to some types of honeycomb core. This material may be a viable candidate for struct
37、ural aerospace applicationswhenever a core or filler is needed and in nonstructural applicationsincluding formed configurations. Polymethacrylimide (PMI) foam has been usedto comply with the requirements of this specification.6.2 Acquisition requirements . Acquisition documents should specify thefol
38、lowing:a. Title, number and date of the specificationb. Type and class of material (see 1.2)c. Issue of DoDISS to be cited in the solicitation, and if required,the specific issue of individual documents referenced (see 2.2).d. When first article is required (see 3.1).e. Dimensions in SI and English
39、units.f. Sampling plan, if other than specified in 4.4g. Packaging requirements (see 5.1).6.3 Procedure for drying type I and type II foams . Dry foam sections andpanels in an air circulating oven at 250 + 10 o F (121 + 5 o C) for a minimum of 2hours. Do not allow panels to come in contact with othe
40、r panels in the oven(do not stack panels). Separate each panel from the closest panel by not lessthan one inch (2.5 cm). Arrange panels parallel to the direction of air flow.Do not place panels directly on the bottom of the oven, or on any other pieceof nonperforated metal (which could restrict air
41、flow). Place a piece ofperforated metal or heavy metal screen atop the panel to prevent warpageduring the drying cycle.6.4 Procedure for heat treating type II foams . Prior to heat treating, drythe material in accordance with 6.3. Heat treat the material immediately afterthe drying cycle for the fol
42、lowing times and temperatures: 48 hours 350 +10 o F (177 + 5 o C) for class 2 and 3, 20 hours 320 + 10 o F (160 + 5 o C) followedby 28 hours 350 + 10 o F (177 + 5 oC) for class 4 and 5, and 24 hours 350 +10 o F (177 + 5 oC) for class 6. Do not allow panels to come in contact withother panels in the
43、oven (do not stack panels), and separate each panel fromthe closest panel by not less than one inch (2.5 cm). Arrange panels parallelto the direction of air flow. Do not place panels directly on the bottom ofthe oven, or on any other piece of nonperforated metal (which could restrictair flow). Place
44、 a piece of perforated metal or heavy metal screen on bothProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-6MIL-PRF-46194Asides of each panel to prevent warpage during the heat treating cycle. Heattreating is a processing step involving extended expos
45、ure of foam to elevatedtemperatures; heat treat under highly controlled conditions to ensuredimensional stability of the foam. 6.5 Subject term (key word) listing .Honeycomb corePolymethacrylimideCustodians: Preparing activity:Army - MR Army - MRNavy - ASAir Force - 11Project No. CMPS-0136Review act
46、ivities:Army - AT, AV, IENavy - SHAir Force - 13DLA - DHProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-7MIL-PRF-46194ATABLE I. Physical properties of rigid foam .Class Density Water Absorption (%), Max 1 /lb m /ft 3 (kg/m 3 ) Type I Type II1 1.56 to
47、 2.44 (25.0 - 39.1) 13 -2 2.45 to 3.85 (39.2 - 61.7) 13 103 3.86 to 5.59 (61.8 - 89.5) 13 104 5.60 to 8.20 (89.7 - 131.3) - 105 10.60 to 15.00 (169.8 - 240.3) - 106 15.60 to 21.80 (249.9 - 349.2) - 101 / The procedure in paragraph 4.5 shall be used to determine water absorption.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-
