理化检验-物理分册2017，Vol.53Issue(5)：309-313,352,6.DOI:10.11973/lhjy-wl201705002
铝合金钻杆旋转弯曲疲劳断口特征
Fatigue Fracture Characteristic of Aluminum Alloy Drill Pipes after Rotating Bending
摘要
Abstract
Rotary bending fatigue tests were conducted on aluminum alloy drill pipes under different stress amplitude firstly,and then the micro fracture characteristic of the fatigue samples under high and low stress was observed by scanning electron microscope.The results show that:under the low stress of 170 MPa,the fracture surface was mainly divided into three zones as the crack initiation zone,steady crack propagation zone and instantaneous fracture zone;the fatigue cracks initiated on phase boundary of subsurface,and the crack stable propagation zone was large and the area was more than 60％;while under the high stress of 290 MPa,multi crack sources appeared on fracture surface,and the micro cracks formed on surface or subsurface,and the crack propagation zone was only 15％～30％.For the same sample,with the propagation of fatigue cracks,the fatigue glide steps on the fracture surface broadened and the fatigue strips got clear.For different samples,with increase of the stress,crack propagation rate increased and the fatigue glide strip space broadened,and the secondary fatigue cracks were easier to appear.The area of crack propagation zone decreased evidently and the corresponding fatigue life dramatically reduced.关键词
铝合金钻杆/疲劳断口/疲劳裂纹/萌生/扩展Key words
aluminum alloy drill pipe/fatigue fracture/fatigue crack/initiation/propagation分类
矿业与冶金引用本文复制引用
舒志强,袁鹏斌,欧阳志英,龚丹梅,余荣华,曹晶晶..铝合金钻杆旋转弯曲疲劳断口特征[J].理化检验-物理分册,2017,53(5):309-313,352,6.基金项目
上海市宝山区科技创新专项资金资助项目(13-B-3) （13-B-3）
