ASTM_D_1674_-_67_1977_scan.pdf

ASTM DI679 67 H 0757530 0022720 1 I&-69-0/Designation:D 1674-67(Reapproved 1977)Standard Methods of Testing POLYMERIZABLE EMBEDDING COMPOUNDS USED FOR ELECTRICAL INSULATION This standard is issued under the fixed designation D 1674;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(E)indicates an editorial change since the lasf revision or reapproval.1.Scope 1.1 These methods cover electrical,mechani-cal,and thermal tests for polymerizable com-pounds used for encasing or embedding electrical and electronic components or assemblies.The procedures appear in the following sections:Electrical Insulating Materials at Commer-cial Power Frequencies D 150 Test Methods for A-c LoSS Character-istics and Permittivity(Dielectric Constant)of Solid Electrical Insulating Materials*D229 Method of Testing Rigid Sheet and Plate Materiais Used for Electrical Insu-Sampling.3 D 374 Test Methods for Thickness of Solid Specimen Preparation and Electrical Insulation ASTM Procedure Sections Method 1ati0n3.Conditioning.4 D618 Hardness.5 to 11 D2240 Coeficient of Linear Thermal Expansion.12 to 18 D 696 Specific Gravity.19 to 26 D 792 Conductivity.27 to 33.Thermal Shock Resistance.34 to 39.Dielectric Constant and Dissipa-tion Factor.40 to 48.Dielectric Strength.49 to 55.Arc Resistance.56 to 60 D 495 Effect of High Humidity.6 1 to 66.Flame Resistance(ignition time and burning time).67 D 229 Dielectric Strength of Embedded Electrodes.68 to 75 D 149 1,2 The compounds must cure without pres-sure and may or may not require heat to accom-plish the reaction.They are required to electri-cally insulate and mechanically protect and sup-port the parf or assembly without a case,pot,or other external reinforcement after curing.1.3 The values states in inch-pound units are to be regarded as the standard.2.Applicable Documents 2.1 ASTMStandards:D 149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid.Coefficient of Thermal 7 D495 Test Method for High-Voltage,Low-Current Dry Arc Resistance of Solid Elec-trical Insulation D 6 I8 Methods of Conditioning Plastics and Electrical Insulating Materials for Testing D 696 Test Method for Coefficient of Linear Thermal Expansion of Plastics4 D 792 Test Methods for Specific Gravity and Density of Plastics by Displacement4 D2240 Test Method for Rubber Property-Durometer Hardness E 197 Specification for Enclosures and Serv-icing Units for Tests Above and Below Room Temperature6 3.Sampling 3.I Because of the diverse nature of the com-These methods are under the jurisdiction of ASTM Com-mittee D-9 on Electrical Insulating Materials and are the direct responsibility of Subcommittee W9.01 on Electrical Insulating Varnishes,Powders,and Encapsulating Compounds.Current edition approved Sept.8,1967.Published November 1967.Originally published as D 1674-59.Last previous edition D 1674-66.Annual Book OfASTMStatidards,vbl 10.02.Aiinrial Book o f ASTMSlatidards,Vol 10.01.Antiiral Book o f ASTM Standards,Vol 08.01.Annual Book ofASTM Siandards,Vol 09.01.Discontinued,see 1980 Atinital Book of ASTMStatidards,Part 12.-m J 360 NOTICE:This standard has either been superseded and replaced by a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information.ASTM Dlb74 67.I 0757530 0022723 3 I DI674 pounds,and the various forms and packages of ner and under the conditions specified in Section resins,hardeners,catalysts,etc.,commercially.6.available,no standard methods of sampling have been established.An adequate amount of mate-rial,representative of each ingredient,shall be selected from each lot to permit preparation of specimens in accordance with Section 4.3.2 Ingredients shall not be used beyond the shelf life designated by the manufacturer.4.Specimen Preparation and Conditioning 4.1 Mold-Slab specimens shall be cast in a verfical position in any suifable mold which will result in castings of a thickness which can be controlled within I 5%,The mold may consist of two highly polished plates,YS in.(9.5 mm)thick,coated with a suitable release agent and spaced to the desired specimen thicknesswith a U-shaped spacer of any suitable material to which the compound will not adhere.The mold assembly shall be clamped together with suffi-cient pressure to prevent leakage of the com-pound,A mold to produce 6 by 6-in.(152 by 152 mm)specimens is conveniently handled.The resulting cast slabs shall then be cut into the size specimens required.4.2 Casting-The compound ingredients shall be mixed in accordance with the manufac-turers directions,then poured into the molds.When the ingredients are mixed above ambient temperature,the molds shall be preheated ap-proximately 10C above the mixing temperature before the mixture is poured into the molds.In pouring,precautions shall be taken to avoid en-trapping of air.Specimens