简介：Threedifferenttypesoftensilestrength(TS)980MPagradeadvancedhigh-strengthsteelsusedinautomotiveapplications,namely,980MS(martensitesteel),980DP(dualphase)and980QP(quenchingandpartitioning)steelswereexamined.ThedelayedfractureresistanceofthesteelswasevaluatedusingaU-bendtest,slowstrainratetest(SSRT)andaconstantloadtensiletest.Theresultsindicatedthatallthesteelscouldpassthe300hHClsolutionimmersiontestandnoneoftheU-bendspecimenswasfracturedinthetest.However,thesteelsexhibiteddifferentsusceptibilitiestodelayedfractureunderSSRTandtheconstantloadtensiletests.980DPexhibitedthehighestresistancetodelayedfractureamongallthesamples,while980MSwasfoundtobethemostsusceptibletodelayedfracture.

简介：Plainconcreteisregardedasatwo-phasematerialcomprisingrandomlydistributedaggregatesandmortarmatrix.Aseriesofthree-pointbendingconcretebeamswithsymmetricorasymmetricdoublenotchesaremodeledusingthemodifiedrandomaggregategenerationandpackingalgorithm.Thecohesivezonemodelisusedasthefracturecriterionandthecohesiveelementsareinsertedintoboththemortarmatrixandtheaggregate-mortarinterfacesaspotentialmicro-crackingzones.Thedeadandalivecrackphenomenaarestudiedexperimentallyandnumerically;andtheinfluencesofnotchlocation,aggregatedistributionandgradationonfracturearenumericallyevaluated.Someimportantconclusionsaregiven.

简介：TheCu/Sn-3.OAg-0.5Cu/Cubuttingsolderjointswerefabricatedtoinvestigatetheevolutionoftheinterfacialintermetalliccompound(IMC)andthedegradationofthetensilestrengthofsolderjointsundertheeffectofelectromigration(EM)andagingprocesses.Scanningelectronmicroscopy(SEM)resultsindicatedthattheCu_6Sn_5interfacialIMCpresentedobviousasymmetricalgrowthwiththeincreaseofEMtimeundercurrentdensityof1.78×10~4A/cm~2at100℃,andthegrowthofanodicIMCpresentedaparabolicrelationshipwithtimewhilethecathodicIMCgotthinnergradually.However,asforagingsamplesat100℃withoutcurrentstressing,theCu_6Sn_5IMCpresentedasymmetricalgrowthwithaslowerratethantheanodicIMCofEMsamples.Thetensileresultsindicatedthatthetensilestrengthofthesolderjointsundercurrentstressdeclinedmoredrasticwithtimethantheagingsamples,andthefracturemodetransformedfromductilefracturetobrittlefracturequicklywhilethefracturemodeofagingsamplestransformedfromcup-coneshapedfracturetomicroporousgatheringfractureinaslowway.

简介：在典型周期的装载下面的near-alpha钛合金的疲劳行为上的试验性的调查被执行模仿装载在引擎片上使用的状态的服务。低周期的疲劳(LCF)测试的轴的控制压力的紧张紧张在最大的压力和压力比率的一个范围上被执行。旋转弯曲测试用一个装载步的过程被进行揭示高周期的疲劳(HCF)限制压力。周期的弄软效果在这材料被观察，并且紧张ratcheting在900装载的最大的LCF显然发生?MPa。LCF抵抗被发现依赖于装载的最大值和压力比率。为1的HCF限制压力?NA被货车derWaals力量鰨?鰨主要地管理？？

简介：在从Libixia节的Jialingjiang形成的破裂的大多数静脉mineralsdeposited，Hechan区域包括大量僵绳白云石和伴随的天青石，方解石和荧石。这研究分析了性质，来源，由飞机光岩相学的液体的进化，液体包括方法，阴极射线发光图象，和稳定的同位素的作文。在白云石的二阶段的水的液体包括的homogenization温度在100和270°C之间变化。与δ18O数据，为破裂屑的降水负责的液体有δ18在10‰之间的O值并且18‰(相对降雪)。僵绳白云石和伴随的矿物质是在提高的温度的稠密的盐水的活动的结果。而且，液体从导出水兵的盐水的混合物被导出并且更深传播的分析表演流动。这液体在成岩作用期间在Sr被充实并且在骨折并且为地区性的矿化作用形成了天青石。僵绳白云石的溶解被归因于冷却Mg/Ca-decreased液体，它可以联系到一在包围碳酸盐石膏沥滤到天青石。