Crack opening displacement(COD) was applied to characterize the fracture initiation of the tough high density polyethylene. Normal single side notched three point bend specimens and silica rubber replica techniques ...Crack opening displacement(COD) was applied to characterize the fracture initiation of the tough high density polyethylene. Normal single side notched three point bend specimens and silica rubber replica techniques were used to study the characteristic COD of high density polyethylene pipe and its butt fusion joints including the weld fusion zone and heat affected zone at different temperature from -78 ℃ to 20 ℃ . Testing results show that the characteristic COD appears to depend on the structural features that are determined by welding process and the testing temperature. As the temperature is lowered, the characteristic COD of all zones studied decreases. Because the welding process significantly changes some structural feature of the material, characteristic COD of the weld fusion zone is the smallest one among those of the three zones. The results can be used for the engineering design and failure analysis of HDPE pipe.展开更多
以裂纹张开位移(crack open ing d isp lacem ent)特征值参量为基础,对国内燃气工业中应用日益普及的高密度聚乙烯(HDPE)管道热熔对接接头的抗开裂特性参量的分散性及统计分布进行了研究。结果表明,HDPE热熔对接接头在低温下,其抗开裂...以裂纹张开位移(crack open ing d isp lacem ent)特征值参量为基础,对国内燃气工业中应用日益普及的高密度聚乙烯(HDPE)管道热熔对接接头的抗开裂特性参量的分散性及统计分布进行了研究。结果表明,HDPE热熔对接接头在低温下,其抗开裂参量饱和启裂COD值具有一定的分散性。对其进行拟合统计检验结果表明,三参数威布尔分布为其最佳拟合分布。并且,随着温度的降低,抗开裂参量的数据的分散性变小。展开更多
文摘Crack opening displacement(COD) was applied to characterize the fracture initiation of the tough high density polyethylene. Normal single side notched three point bend specimens and silica rubber replica techniques were used to study the characteristic COD of high density polyethylene pipe and its butt fusion joints including the weld fusion zone and heat affected zone at different temperature from -78 ℃ to 20 ℃ . Testing results show that the characteristic COD appears to depend on the structural features that are determined by welding process and the testing temperature. As the temperature is lowered, the characteristic COD of all zones studied decreases. Because the welding process significantly changes some structural feature of the material, characteristic COD of the weld fusion zone is the smallest one among those of the three zones. The results can be used for the engineering design and failure analysis of HDPE pipe.
文摘以裂纹张开位移(crack open ing d isp lacem ent)特征值参量为基础,对国内燃气工业中应用日益普及的高密度聚乙烯(HDPE)管道热熔对接接头的抗开裂特性参量的分散性及统计分布进行了研究。结果表明,HDPE热熔对接接头在低温下,其抗开裂参量饱和启裂COD值具有一定的分散性。对其进行拟合统计检验结果表明,三参数威布尔分布为其最佳拟合分布。并且,随着温度的降低,抗开裂参量的数据的分散性变小。
