Designation:D796-87a4sbStandardPracticeforCompressionMoldingTestSpecimensofPhenolicMoldingCompounds’ThisstandardisissuedunderthefixeddesignationD796;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrzvision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsiion(c)indicatesaneditorialchangesincethelastrevisionorreapproval.1.ScQpe1.1ThispracticedescribesproceduresforcompressionmoldingofIzadorCharpyimpact,flexure,tension,com-pression,waterabsorption,modulusintensionorflexure,heataging,electricaltests,andheat-deflectiontemperatures(Note).1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesinparenthesesaregivenforinforma-tiononiy.1.3Thisstandardmayinvolvehazardoitsmaterials,oper-ations,andequìpmertt.Thisstandarddoesnotpurporttoaddressallofttiesafetyproblemsassociatedwithitsuse.Itistheresponsibilityofttieuserofthisstandardtoestablishappropriatesajètyandhealthpracticesanddeterminetheapplicabilityofregirlatoiyliinitationspriortouse.NOTE-Theutilityofthispracticehasbeendemonstratedforthemoldingofphenolicmoldingcompoundsexhibitinghigher-viscosity,non-Newtonianflow.2.ReferencedDocumenfs2.1ASTMStandards:D638TestMethodforTensilePropertiesofPlastics2D647PracticeforDesignofMoldsforTestSpecimensofD651TestMethodforTensileStrengthofMoldedElec-D958PracticeforDeterminingTemperaturesofStandardPlasticMoldingMaterials2tricalInsulatingMaterials3ASTMMoldsforTestSpecimensofPlastics’3.SignificanceandUse3.1Theconditionsunderwhichsamplesaremoldedinfluencethepropertiesofthespecimens.Indeterminingwhetheragivencompoundmeetsthespecificationrequire-ments,itisimportanttoholdtoastandardsetofconditions.Thisisalsonecessaryforavalidcomparisonofpropertiesobtainedwithdifferentcompounds,orbetweenlotsofthesamecompound.3.2Ifthemoldedspecimensshowevidenceoflowdensityareasduetotrappedgases,thespecimensshouldbedis-carded.Inmoldingnewspecimens,themoldshouldbeopenedslightlyjustafteritisclosed.Itshouldbeclosedagainw...
