简介:Finiteelementmethod(FEM)hasbeenusedtoanalyzethestressandstrainfieldsandthestresstri-axiallevelsaroundthetipofthecrackundermode-Ⅱloading.Theresultsshowthat:undermode-Ⅱloading,thedirectionofthemaximumtensilestressandthatofthemaximumtri-axiallevels(R_)existatanangleof-75.3°fromtheoriginalcrackplane:themaximumshearstressandR_=0existalongtheoriginalcrackplane.Mode-ⅡloadingexperimentusingBHW-35steelatdifferenttemperaturesshowthattherearetwokindsoffracturemode.openingmode(ortensilemode)andslidingmode(orshearmode).Ade-creaseintemperaturecausesthefracturemodetochangefromshearmodetotensilemode.ForBHW-35steel,thiscriticaltemperatureisabout-90C.Actually.underanykindofloadingmode(modeⅠ,modeⅡ,modeⅢormixedmode),therealwaysexistseveralkindsofpotenitalfracturemodes(forexample,openingmode.slidingmode.tearingmodeormixedmode).Theeffectoftemperatureundermode-Ⅱloadingisactuallyrelatedtothechangeoftheelastic-plasticpropertiesofthematerial.
简介:这研究的目的是评估本地人爬象粗糙的颗粒的热那样的各种各样的微观结构的损坏影响了地区(CGHAZ),精细的热影响了地区(FGHAZ),intercritical热影响了作为类型IV区域知道的地区(ICHAZ),焊接金属,并且由小穿孔机(SP)基于P92(9Cr-2W)钢焊接的金属爬在600掳C的测试。另外,焊接分开决定最弱的本地人,微观结构在上的效果爬在P92钢的焊接的破裂行为被学习。从试验性的结果,FGHAZ和类型IV区域结果是P92焊接的很弱的本地部分。特别,TYPEIV区域显示出最大的排水量率并且与许多过了最短的破裂生活爬洞广泛地在大多数这个区域传播了。