ASTM_E_1556_-_12.pdf

Designation:E155612Standard Specification forEpoxy Resin System for Composite Skin,HoneycombSandwich Panel Repair1This standard is issued under the fixed designation E1556;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scope1.1 This specification covers the requirements for an epoxyresin system intended for the repair of sandwich panels fordurable,rigidwall,relocatable structures.It must be usable in afield environment and shall not require the use of specialequipment such as autoclaves or presses.The epoxy systemcovered by this specification shall be usable for simultaneousimpregnation of a wet-layup composite skin and bonding ofthat skin to a substrate honeycomb core.The material shallwithstand exposure to temperatures from 54 to 93C(65 to199F)and high relative humidity,and also the combination ofstress,temperature,and relative humidity that are expected tobe encountered in service.1.2 The values stated in SI units are to be regarded asstandard where only SI units are given or where SI units aregiven first followed by inch-pound units;where inch-poundunits are given first followed by SI units,the inch-pound unitsare to be regarded as the standard.1.3 The following safety hazards caveat refers only to thetest methods described in this specification.This standard doesnot purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the user of thisstandard to establish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.2.Referenced Documents2.1 ASTM Standards:2C297/C297M Test Method for Flatwise Tensile Strength ofSandwich ConstructionsD792 Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by DisplacementD2344/D2344M Test Method for Short-Beam Strength ofPolymer Matrix Composite Materials and Their LaminatesD2584 Test Method for Ignition Loss of Cured ReinforcedResinsD2734 Test Methods for Void Content of Reinforced PlasticsD3165 Test Method for Strength Properties of Adhesives inShear by Tension Loading of Single-Lap-Joint LaminatedAssembliesE631 Terminology of Building ConstructionsE1091 Specification for Nonmetallic Honeycomb Core forUse in Shelter PanelsE1749 Terminology Relating to Rigid Wall RelocatableShelters2.2 Military Specifications:3MIL-I-24768 Insulation,Plastic,Laminated,Thermosetting,Glass-Cloth,Epoxy-Resin2.3 Military Standards:3MIL-STD-129 Military Marking for Shipping and StorageMIL-STD-1916 DOD Preferred Methods for Acceptance ofProduct2.4 Commercial Standards:4SAE-AMS-C-9084 Cloth,Glass,Finished for Epoxy ResinLaminates3.Terminology3.1 DefinitionsSee Terminologies E631 and E1749 fordefinitions of general terms used in this specification.4.Physical Requirements4.1 Working Characteristics:4.1.1 ApplicationThe components of the epoxy resin shallbe readily hand-mixed to a smooth consistency suitable forapplication.It shall be uniform and free of lumps.The resincomponents,once mixed,shall not settle out.The epoxy1This specification is under the jurisdiction of ASTM Committee E06 onPerformance of Buildings and is the direct responsibility of Subcommittee E06.53on Materials and Processes for Durable Rigidwall Relocatable Structures.Current edition approved Nov.1,2012.Published December 2012.Originallyapproved in 1993.Last previous edition approved in 2008 as E1556 08.DOI:10.1520/E1556-12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk,DODSSP,Bldg.4,SectionD,700RobbinsAve.,Philadelphia,PA19111-5098,http:/www.dodssp.daps.mil.4Available from Society of Automotive Engineers(SAE),400 CommonwealthDr.,Warrendale,PA 15096-0001,http:/www.sae.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 material shall be suitable for the wet-layup impregnation ofSAE-AMS-C-9084 glass cloth and for application to corematerials over the temperature range of 16 to 38C(60 to100F)and at relative humidities of 30 to 75%.4.1.2 Application LifeThe application life of a 200-g kit ofthe mixed epoxy system shall be at least 60 min when tested inaccordance with 4.1.5.The epoxy shall be considered to havereached the end of its application life when the viscosity of this200-g quantity of mixed adhesive exceeds 20 000 centipoise.4.1.3 CuringThe epoxy system shall be capable of curingat 23 6 2C(73 6 4F)in 7 days,or for no longer than 3 h ata temperature of 60 to 66C(140 to 151F),with a cu