Results 1 to 10 of about 307 (133)
Zhongshan Daxue xuebao. Yixue kexue ban, 1990 本文用牙体光弹性实验研究证实了牙颈部应力集中的客观存在,作者认为:牙颈部长期的应力集中,可能出现疲劳裂纹,如若伴随化学腐蚀的作用(如酸类),则可能加速疲劳裂纹的形成与发展,最终形成楔状缺损。
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Jianzhu Gangjiegou Jinzhan, 2022 采用基于断裂力学的有限元法对焊接H形钢梁的疲劳裂纹扩展过程进行了数值模拟。给出了模型的基本假定：初始裂纹为半径1.016 mm的圆形、裂纹中心位于受拉翼缘与腹板之间焊缝焊根处、裂纹前缘由3~4段1/4椭圆弧线控制、在裂纹前缘端点处与内部点处分别采用不同的Paris公式系数、以疲劳裂纹深度穿透受拉翼缘壁厚或SIF超过断裂韧性为循环终止条件。采用二次多项式外推插值的方式对H形钢梁裂纹前缘端点处以及紧邻端点的个别结点处直接输出的应力强度因子（SIF）计算值进行了修正。通过试验验证 ...
肖顺, 童乐为
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Fatigue behavior of powder metallurgy superalloy FGH97 [PDF]
, 2016 The fatigue crack growth rates of powder metallurgy (P/M) superalloy FGH97 with different grain sizes, γ' phase sizes and Hf contents were measured at a 650℃ high temperature condition and compared with those of FGH95 and FGH96 alloys.
DONG Jian-xin +4 more
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Jianzhu Gangjiegou Jinzhan, 2022 针对钢桥中钢板疲劳裂纹进行了一系列疲劳裂纹修复试验研究，以确定不同修复方法下结构的疲劳性能。高弹模CFRP（碳纤维增强复合材料）修复法是通过粘贴高弹模CFRP布来增大结构刚度，以延长结构疲劳寿命，且碳纤维材料基本不会产生疲劳裂纹，具有较好的抗疲劳效果。采用数值模拟和试验研究相结合的方法，首先对修复钢板的应力分布和特点进行了详细的分析，然后通过3组对比疲劳试验，确定了不同修复方法对损伤钢板疲劳寿命的增强效果。最后利用修复试验值与各国规范规定的S-N曲线进行比较，分析已修复钢板的疲劳性能。研究结果表明 ...
吕志林 +4 more
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High-temperature fracture toughness of high Nb-containing TiAl alloys [PDF]
, 2016 The fracture toughness of a nearly lamellar Ti-45Al-8Nb-0.2W-0.2B-0.1Y alloy and a fully lamellar Ti-45Al-7Nb-0.2W-0.2Hf-0.3B-0.15 C alloy at 750℃ was investigated by prefabricating a fatigue crack in the compact tension(CT) specimen,and the ...
JIAO Ze-hui +4 more
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A fatigue crack quantification model for metallic structure based on strain monitoring data
Xibei Gongye Daxue Xuebao, 2023 Obtaining the real-time fatigue crack length of a metallic structure is the prerequisite of the fatigue life monitoring and residual life estimation for an aircraft.
LI Kunpeng +5 more
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疲劳荷载特性对8.8级M24高强度螺栓疲劳裂纹扩展机理影响探析
Jianzhu Gangjiegou Jinzhan, 2023 为研究常幅疲劳荷载特性对高强度螺栓疲劳裂纹扩展的影响，针对钢结构端板连接用8.8级M24高强度螺栓在不同应力比/应力幅作用下常幅疲劳试验所得到的24个试件断口形貌进行定量分析，并采用ABAQUS软件数值模拟高强度螺栓应力集中情况，探讨含初始裂纹高强度螺栓裂纹尖端应力强度因子与荷载特性、预制裂纹形状之间的关系。结果表明：在轴向受拉疲劳荷载作用下，螺母与螺栓啮合第1圈螺纹处为疲劳断裂最不利位置；试件断口稳定扩展区面积与应力比/应力幅呈负相关，快速扩展区面积与应力比/应力幅呈正相关 ...
樊丽轩 +4 more
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Fatigue Crack Growth Rate Curve Based on the CJP Model and Its Application Method [PDF]
, 2018 Fatigue crack growth rate tests of commercial pure titanium specimens with 5 different height-width ratios of CT specimens using the digital imagine correlation technique are carried out.
YANG, B
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Assessment of wind-induced fatigue crack initiation life at guyed mast earplate joints considering welding residual stresses [PDF]
, 2010 A new method for assessing the degree of the cumulative fatigue crack initiation damage of the welds of earplate joints of a guyed mast,which connect the mast with the cable,is proposed.Based on the multi-scale wind-induced stress analysis of the ...
Pi, Y, Qu, W, Wang, W
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Indentation effect on the fatigue limit of axle steel [PDF]
, 2016 A hardness tester was used to make indentations on the hourglass fatigue specimens of axle steel,and notches were machined by electronic discharge machining(EDM).The fatigue limits of both indentation specimens and notched ones were examined and compared
DAI Guang-ze +4 more
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