本文主要研究内容
作者马洪顺（2019）在《基于裂尖等效蠕变应变的面内与面外统一蠕变拘束参数的研究》一文中研究指出：蠕变裂尖拘束效应对材料与结构的蠕变裂纹扩展速率具有显著的影响,在高温结构完整性设计和评定中,需要准确地纳入这种影响。裂尖拘束分为面内拘束和面外拘束,对于试样和结构中的三维裂纹,面内与面外拘束同时存在,其主要受试样和结构几何、裂纹尺寸及加载方式等的影响。为在含裂纹高温结构的蠕变寿命评价中准确地纳入裂尖拘束的影响,需要研究和发展可同时表征面内与面外统一蠕变拘束的参数。本文通过数值模拟、实验数据和理论分析相结合的方法,主要研究基于裂尖等效蠕变应变的面内与面外统一的蠕变拘束参数Ac;材料的蠕变裂纹扩展速率与统一蠕变拘束参数Ac的关联;参数Ac统一地表征焊接接头裂纹的几何拘束(面内与面外拘束)与材料拘束的能力;基于参数Ac的含轴向和环向内表面裂纹承压管道的拘束表征和拘束参数解等。论文主要研究工作与结果如下:(1)采用基于延性耗竭蠕变损伤模型的有限元法模拟得到了不同面内和面外拘束C(T)试样的蠕变裂纹扩展速率,有限元计算了这些试样裂尖前的等效蠕变应变。基于裂尖前等效蠕变应变等值线所围的面积,研究定义了一个可同时表征面内与面外蠕变拘束的统一拘束参数Ac。参数Ac可与不同面内和面外拘束试样的蠕变裂纹扩展速率形成统一的关联线,表明Ac对面内和面外拘束同样敏感,其是一个可以统一表征面内和面外蠕变拘束的参数。进一步分析表明,参数Ac与载荷水平无关,与蠕变时间(t/tred>0.7)无关,与等效蠕变应变δc等值线的选取无关。参数Ac的这些特征使其便于进行拘束分析和工程应用。(2)通过三维有限元法,计算了不同几何和加载方式试样的拘束参数Ac,探明了参数Ac沿不同试样厚度的分布规律及试样尺寸的影响规律。对比分析了参数Ac和基于裂尖应力场的蠕变拘束参数R*、h和表征不同几何和加载方式试样的宽范围面内和面外拘束的能力。结果进一步表明,基于裂尖等效蠕变应变的参数Ac可用来准确定量地表征不同试样中宽范围的面内和面外拘束及其交互作用。(3)基于不同几何和加载方式试样的拘束参数Ac的计算,并结合文献中这些试样的蠕变裂纹扩展速率的实验数据和本文的数值模拟数据,研究建立了Cr-Mo-V钢和316H钢的蠕变裂纹扩展速率与拘束参数Ac的统一关联式。由关联式预测的不同几何试样的蠕变裂纹扩展速率与实验数据吻合。该关联式可望用于含裂纹高温结构的蠕变裂纹扩展寿命评价中,以提高评价的准确性。(4)采用延性耗竭蠕变损伤模型的有限元法模拟得到了不同面内和面外拘束水平焊接接头C(T)试样的蠕变裂纹扩展速率,并计算了参数Ac值。研究了参数Ac统一表征焊接接头裂纹的儿何和材料复合拘束的能力。结果表明,随几何拘束和材料拘束的增加,蠕变裂纹扩展速率加快;参数Ac可以同时表征焊接接头裂纹的几何拘束(面内和面外拘束)和材料蠕变性能失配引起的材料拘束效应。基于参数Ac建立了P92钢焊接接头裂纹的几何与材料统一拘束与蠕变裂纹扩展速率的关联式。(5)基于参数Ac,对含轴向和环向内表面裂纹承压管道的拘束进行了三维有限元计算表征。计算结果表明,裂纹前沿较深处的蠕变拘束水平比自由表面附近高,参数Ac可以表征管道表面裂纹的面内和面外蠕变拘束。管道裂纹的拘束水平随裂纹深度a/t的增加和裂纹深长比a/c的减小而增大,随管道径厚比Ri/t和壁厚t的增大而升高。计算得到了管道裂纹的拘束参数Ac的有限元解,并拟合得到了计算管道裂纹前沿最深点、表面点及裂纹前沿平均拘束值的经验公式。
Abstract
ru bian lie jian ju shu xiao ying dui cai liao yu jie gou de ru bian lie wen kuo zhan su lv ju you xian zhe de ying xiang ,zai gao wen jie gou wan zheng xing she ji he ping ding zhong ,xu yao zhun que de na ru zhe chong ying xiang 。lie jian ju shu fen wei mian nei ju shu he mian wai ju shu ,dui yu shi yang he jie gou zhong de san wei lie wen ,mian nei yu mian wai ju shu tong shi cun zai ,ji zhu yao shou shi yang he jie gou ji he 、lie wen che cun ji jia zai fang shi deng de ying xiang 。wei zai han lie wen gao wen jie gou de ru bian shou ming ping jia zhong zhun que de na ru lie jian ju shu de ying xiang ,xu yao yan jiu he fa zhan ke tong shi biao zheng mian nei yu mian wai tong yi ru bian ju shu de can shu 。ben wen tong guo shu zhi mo ni 、shi yan shu ju he li lun fen xi xiang jie ge de fang fa ,zhu yao yan jiu ji yu lie jian deng xiao ru bian ying bian de mian nei yu mian wai tong yi de ru bian ju shu can shu Ac;cai liao de ru bian lie wen kuo zhan su lv yu tong yi ru bian ju shu can shu Acde guan lian ;can shu Actong yi de biao zheng han jie jie tou lie wen de ji he ju shu (mian nei yu mian wai ju shu )yu cai liao ju shu de neng li ;ji yu can shu Acde han zhou xiang he huan xiang nei biao mian lie wen cheng ya guan dao de ju shu biao zheng he ju shu can shu jie deng 。lun wen zhu yao yan jiu gong zuo yu jie guo ru xia :(1)cai yong ji yu yan xing hao jie ru bian sun shang mo xing de you xian yuan fa mo ni de dao le bu tong mian nei he mian wai ju shu C(T)shi yang de ru bian lie wen kuo zhan su lv ,you xian yuan ji suan le zhe xie shi yang lie jian qian de deng xiao ru bian ying bian 。ji yu lie jian qian deng xiao ru bian ying bian deng zhi xian suo wei de mian ji ,yan jiu ding yi le yi ge ke tong shi biao zheng mian nei yu mian wai ru bian ju shu de tong yi ju shu can shu Ac。can shu Acke yu bu tong mian nei he mian wai ju shu shi yang de ru bian lie wen kuo zhan su lv xing cheng tong yi de guan lian xian ,biao ming Acdui mian nei he mian wai ju shu tong yang min gan ,ji shi yi ge ke yi tong yi biao zheng mian nei he mian wai ru bian ju shu de can shu 。jin yi bu fen xi biao ming ,can shu Acyu zai he shui ping mo guan ,yu ru bian shi jian (t/tred>0.7)mo guan ,yu deng xiao ru bian ying bian δcdeng zhi xian de shua qu mo guan 。can shu Acde zhe xie te zheng shi ji bian yu jin hang ju shu fen xi he gong cheng ying yong 。(2)tong guo san wei you xian yuan fa ,ji suan le bu tong ji he he jia zai fang shi shi yang de ju shu can shu Ac,tan ming le can shu Acyan bu tong shi yang hou du de fen bu gui lv ji shi yang che cun de ying xiang gui lv 。dui bi fen xi le can shu Ache ji yu lie jian ying li chang de ru bian ju shu can shu R*、hhe biao zheng bu tong ji he he jia zai fang shi shi yang de kuan fan wei mian nei he mian wai ju shu de neng li 。jie guo jin yi bu biao ming ,ji yu lie jian deng xiao ru bian ying bian de can shu Acke yong lai zhun que ding liang de biao zheng bu tong shi yang zhong kuan fan wei de mian nei he mian wai ju shu ji ji jiao hu zuo yong 。(3)ji yu bu tong ji he he jia zai fang shi shi yang de ju shu can shu Acde ji suan ,bing jie ge wen suo zhong zhe xie shi yang de ru bian lie wen kuo zhan su lv de shi yan shu ju he ben wen de shu zhi mo ni shu ju ,yan jiu jian li le Cr-Mo-Vgang he 316Hgang de ru bian lie wen kuo zhan su lv yu ju shu can shu Acde tong yi guan lian shi 。you guan lian shi yu ce de bu tong ji he shi yang de ru bian lie wen kuo zhan su lv yu shi yan shu ju wen ge 。gai guan lian shi ke wang yong yu han lie wen gao wen jie gou de ru bian lie wen kuo zhan shou ming ping jia zhong ,yi di gao ping jia de zhun que xing 。(4)cai yong yan xing hao jie ru bian sun shang mo xing de you xian yuan fa mo ni de dao le bu tong mian nei he mian wai ju shu shui ping han jie jie tou C(T)shi yang de ru bian lie wen kuo zhan su lv ,bing ji suan le can shu Aczhi 。yan jiu le can shu Actong yi biao zheng han jie jie tou lie wen de er he he cai liao fu ge ju shu de neng li 。jie guo biao ming ,sui ji he ju shu he cai liao ju shu de zeng jia ,ru bian lie wen kuo zhan su lv jia kuai ;can shu Acke yi tong shi biao zheng han jie jie tou lie wen de ji he ju shu (mian nei he mian wai ju shu )he cai liao ru bian xing neng shi pei yin qi de cai liao ju shu xiao ying 。ji yu can shu Acjian li le P92gang han jie jie tou lie wen de ji he yu cai liao tong yi ju shu yu ru bian lie wen kuo zhan su lv de guan lian shi 。(5)ji yu can shu Ac,dui han zhou xiang he huan xiang nei biao mian lie wen cheng ya guan dao de ju shu jin hang le san wei you xian yuan ji suan biao zheng 。ji suan jie guo biao ming ,lie wen qian yan jiao shen chu de ru bian ju shu shui ping bi zi you biao mian fu jin gao ,can shu Acke yi biao zheng guan dao biao mian lie wen de mian nei he mian wai ru bian ju shu 。guan dao lie wen de ju shu shui ping sui lie wen shen du a/tde zeng jia he lie wen shen chang bi a/cde jian xiao er zeng da ,sui guan dao jing hou bi Ri/the bi hou tde zeng da er sheng gao 。ji suan de dao le guan dao lie wen de ju shu can shu Acde you xian yuan jie ,bing ni ge de dao le ji suan guan dao lie wen qian yan zui shen dian 、biao mian dian ji lie wen qian yan ping jun ju shu zhi de jing yan gong shi 。
论文参考文献
论文详细介绍
论文作者分别是来自华东理工大学的马洪顺，发表于刊物华东理工大学2019-07-16论文，是一篇关于等效蠕变应变论文,面内与面外拘束论文,统一蠕变拘束参数论文,有限元计算论文,蠕变裂纹扩展速率论文,管道裂纹论文,华东理工大学2019-07-16论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自华东理工大学2019-07-16论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：等效蠕变应变论文; 面内与面外拘束论文; 统一蠕变拘束参数论文; 有限元计算论文; 蠕变裂纹扩展速率论文; 管道裂纹论文; 华东理工大学2019-07-16论文;