ONR 25194 Determination of the resistance to slow crack growth of PE with CRB specimens 翻译

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1、Determinationoftheresistancetoslowcrackgrowthofpolyethylenewithcrackedroundbar(CRB)specimens聚乙烯CRB试样抵抗慢速裂纹扩展的测试Content目录FOREWARD前言1.Scope范围2.Normativereferences引用标准3.Termsanddefinitions术语和定义4.Principle原理5.Testequipment测试设备6.Testspecimen测试试件7.Testprocedure测试程序8.Testreport测试报告Co

2、mparisonofdifferentspecimengeometries不同试样几何形状对比Bibliography参考文献Foreword前言Theknowledgeabouttheresistanceagainstlong-termfailuremechanismscausedbycrackinitiationandslowcrackgrowth(SCG)isanimportantinformationfortherankingandpre-selectionofthermoplasticmaterials,especiallyforlong

3、-termapplicationslikeburiedpipesmadeofpolyethylene.Severalteststodeterminetherelevantfailuremechanismsareavailabletoday,whereelevatedtemperaturesandalsothecombinationwithstresscrackingliquidsareusedtodecreasethetimeframefortesting.由裂纹萌生和慢性裂纹扩展引起的抵抗长期失效机制的认识，对于热塑性材料（特别是如埋于地下长期使

4、用的聚乙烯管）的分类和预选，是一项重要信息。现阶段有测定相关失效机制的实验可利用，在这些实验中，通过提高实验温度和添加应力开裂液缩短了实验持续时间。However,developmentsinmodernrawmaterialshaveledtoasignificantincreaseofthematerialresistanceagainstcrackinitiationandSCG,sothattestingwithavailablemethodsexceedspracticaltimeframes.Thereforenewaccelerati

5、onmethodspreferablyatapplicationrelevanttemperaturesandwithoutadditionaltimereducingliquidsarerequired.然而，现代原材料的发展使得材料对于抵抗裂纹萌生和慢速裂纹扩展，有显著提高，使得已有方法的测试时间超出了实际合理时间范围。因此，现在要求应用一种新型快速合适的且在相关温度下无需添加时间缩短液的实验方法。ThisONR,elaboratedbytheTechnicalCommittee005“Thermoplasticpipesforthetrans

6、portoffluidsandgases”,providesatestmethodtoachieveasignificantdecreaseoftestingtime,evenatambienttemperaturesof23°C,whichisveryclosetothoseofmanyapplications,andwillnotchangethestructuralstatusofthepolymer.Ontheonehandaccelerationofmaterialtestingisreachedbythespecimengeometry

7、.Ontheotherhandthecyclicloadisresponsibleforrelativelyshorttestingtimes.ONR提供了一种方法以实现测试时间的显著减少，甚至在周围环境温度23°C时（非常接近那些实际应用),并且不会改变聚合物的机构状态。ONR在“用以运输液体和气体的热塑性管路”技术会议上详细讲述。一方面，材料测试加快通过试样几何结构达到。另一方面，循环载荷也使测试时间相对缩短。1Scope范围ThisONRspecifiesamethodformeasuringtheresistanceagainstcrack

8、initiationandslowcrackgrowth(SCG).Thisrelevantlong-termfailur