资源描述：
《ASTM D256 Impact resistance of plastic》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、Designation:D256–97AnAmericanNationalStandardAMERICANSOCIETYFORTESTINGANDMATERIALS100BarrHarborDr.,WestConshohocken,PA19428ReprintedfromtheAnnualBookofASTMStandards.CopyrightASTMStandardTestMethodsforDeterminingtheIzodPendulumImpactResistanceof1PlasticsThisstandardisiss
2、uedunderthe®xeddesignationD256;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevi
3、sionorreapproval.1.ScopeMethodoffabrication,includingbutnotlimitedtoprocessingtechnology,moldingconditions,molddesign,andthermal1.1Thesetestmethodscoverthedeterminationofthetreatments;resistanceofplasticstoªstandardizedº(seeNote1)pendulum-Methodofnotching;typehammers,mo
4、untedinªstandardizedºmachines,inbreak-Speedofnotchingtool;Designofnotchingapparatus;ingstandardspecimenswithonependulumswing.Thestan-Qualityofthenotch;dardtestsforthesetestmethodsrequirespecimensmadewithTimebetweennotchingandtest;amillednotch(seeNote2).InTestMethodsA,C,
5、andD,theTestspecimenthickness,Testspecimenwidthundernotch,andnotchproducesastressconcentrationthatincreasestheprob-Environmentalconditioning.abilityofabrittle,ratherthanaductile,fracture.InTest1.2ThevaluesstatedinSIunitsaretoberegardedastheMethodE,theimpactresistanceiso
6、btainedbreakagebystandard.Thevaluesgiveninparenthesesareforinformation¯exuralshockasindicatedbytheenergyextractedfrombyonly.reversingthenotchedspecimen180°intheclampingvise.The1.3Thisstandarddoesnotpurporttoaddressalloftheresultsofalltestmethodsarereportedintermsofenerg
7、ysafetyconcerns,ifany,associatedwithitsuse.Itistheabsorbedperunitofspecimenwidthorperunitofcross-responsibilityoftheuserofthisstandardtoestablishappro-sectionalareaunderthenotch.(SeeNote3.)priatesafetyandhealthpracticesanddeterminetheapplica-NOTE1ÐThemachineswiththeirpe
8、ndulum-typehammershavebeenbilityofregulatorylimitationspriortouse.ªstandardizedºinthattheymustcomplywithcertai
