| 1. | Constitutive model for cyclic softening behavior of 45 steel under uniaxial cyclic straining
45钢单轴应变循环软化行为的本构模型 |
| 2. | The second stage is a cyclic softening course , and what ' s more , the greater the strain amplitude , the greater the trend of softening
在所有试验条件下合金的疲劳硬化阶段都很短暂，疲劳寿命的极大部分是消耗在缓慢的循环软化阶段。 |
| 3. | Then , a logic computational diagram is constructed for calculating diametral growth by assuming fatigue cyclic softening , namely yield strength reduction as tubing fatigues
再通过合理的假设，建立用于计算直径增长的计算机逻辑框图。 |
| 4. | The model results show that when the ct is cycled under the action of an internal pressure , fatigue cyclic softening inevitably leads to the diametral growth
理论模型计算结果表明，当连续油管在内压下循环弯曲时，疲劳循环屈服强度衰减不可避免地导致直径增长。 |
| 5. | In this article , a new theoretical model on diametral growth ( or ballooning ) of coiled tubing ( ct ) under the action of an internal pressure is derived based on fatigue cyclic softening and elasticity and deformation plasticity theories
根据疲劳循环屈服强度衰减模型和弹塑性变形理论，推导了连续油管在内压作用下的直径增长（鼓胀）的理论模型。 |
| 6. | Abstract : in this article , a new theoretical model on diametral growth ( or ballooning ) of coiled tubing ( ct ) under the action of an internal pressure is derived based on fatigue cyclic softening and elasticity and deformation plasticity theories
文摘:根据疲劳循环屈服强度衰减模型和弹塑性变形理论，推导了连续油管在内压作用下的直径增长（鼓胀）的理论模型。 |
| 7. | In addition , the cyclic softening under the strain amplitude less than 0 . 8 % can be explained by " grain - rotation induced cyclic softening " , and the cyclic hardening in the higher strain amplitude was attributed to twinning
在低应变幅区，合金在室温下的低周疲劳性能明显优于在400下的低周疲劳性能。但随着应变幅的增加，室温和400下合金的疲劳寿命趋于接近。 |
| 8. | It can be noticed that both r and t specimens show initial hardening and subsequent softening at the strain amplitude higher than 0 . 8 % and cyclic softening from the beginning to fracture under strain amplitude less than 0 . 8 % at room temperature , and the cyclic flow stress was always lower in r specimen than in t specimen at the same strain range
且在相同的应变幅下， t向试样比r向试样具有更高的循环流变应力。此外，对r向及t向试样，低应变幅下呈现出循环软化现象是因为晶粒旋转导致循环软化；而在高应变幅下发生循环硬化是由于孪晶作用的结果。 |
| 9. | For the cyclic deformation under a given strain at room temperature , cyclic softening is usually displayed till to failure in the lower range of strain ; however , cyclic hardening is displayed in the early stage in the higher range of strain , subsequent cyclic softening in the later stage and till to failure
对于室温下恒应变幅的循环变形，在应变幅较低时表现为循环软化直至疲劳破坏;在应变幅较高时，循环变形的初期为循环硬化，随后是循环软化直至疲劳破坏。 |
| 10. | The alloys , which were cold - worked followed by recrystallization annealing , display cyclic softening in the range of low strain because the cyclic stress - strain curve lies below the monotonic stress - strain curve , and show cyclic hardening in the range of high strain because the cyclic stress - strain curve lies above the monotonic stress - strain curve
在低应变范围，冷加工后经再结晶退火处理的错合金的循环应力一应变曲线位于单调拉伸曲线的下方，表现为循环软化;在高应变范围则位于单调拉伸曲线的上方，表现为循环硬化。 |
