摘要
针对不同干涉量的7050-T7451双剪接头,进行疲劳试验,对比分析了不同干涉量接头的疲劳寿命。通过扫描电镜(SEM)方法,研究了干涉接头疲劳断口形貌特征。研究结果表明:采用干涉量0.08 mm^0.14 mm对7050-T7451板材双剪接头进行干涉安装,可取得较好的疲劳强化效果,并且在0.11 mm干涉量下,疲劳寿命增益最显著。7050-T7451双剪接头试样疲劳断口呈现混合型穿晶疲劳断裂特征,材料具备一定韧性。干涉螺接对孔壁有强化作用,干涉螺接的试片裂纹源于结构表面,而不源于孔壁,结构表面的改进将有利于疲劳寿命的提高。
Fatigue tests were carried out for 7050-T7451 double-shear joints with different interferences and the fatigue life of joints was analyzed. Fatigue fracture behavior morphology characteristics of interference-fit bolted joints were studied with scanning electron microscope. The results show that 7050-T7451 double-shear bolted joints will obtain long fatigue life with interference of 0. 08 ~ 0. 14 mm,and the fatigue life of the joint with 0. 11 mm interference is the longest. The fatigue crack fractography presents hybrid transgranular fracture characteristics and the material of 7050-T7451 has good toughness. Interference-fit bolted jointing can strengthen the wall of hole and make fatigue crack source from the surface of structure,not the wall of hole. The improvement of structure surface can benefit for increasing the fatigue life of joints.
出处
《机械科学与技术》
CSCD
北大核心
2015年第5期808-811,共4页
Mechanical Science and Technology for Aerospace Engineering
关键词
干涉
强化
螺接
疲劳寿命
失效分析
断口
疲劳裂纹源
孔
bolted joints
crack fractography
design of experiments
failure analysis
fatigue crack source
fatigue life
fatigue of materials
hole
interference
morphology
probability distribations
scanning electron microscopy
strengthen
titanium alloys
