内部氢对奥氏体不锈钢拉伸断口分形维数的影响

Effects of Inner Hydrogen on Fracture Fractal Dimension of Austenitic Stainless Steels Tensile Specimens

采用热充氢方法研究了1Cr18Ni9Ti、21Cr6Ni9Mn、Fe31Cr14Ni奥氏体不锈钢的氢脆性能。采用垂直截面法测量了不同热充氢时间拉伸试样的断口分形维数,分析了材料氢脆性能与分形维数的相关性。研究表明:随着充氢时间的延长,3种材料内部氢含量增加、断面收缩率降低、氢致塑性损减增加。反映在断口分形维数上,表现为断口分形维数随充氢时间的延长而降低,且断口分形维数与其断面收缩率呈线性相关。断口分形维数能够描述氢对材料性能的影响。

Properties of hydrogen embrittlement of 1Crl 8Ni9Ti, 21Cr6Ni9Mn and Fe31Cr14Ni austenitic stain less steels were investigated by hydrogen atmosphere thermal charging. At the same time, the fracture fractal dimen- sions of samples in different hydrogen-charging time were measured using the vertical section method. The relationship between fractal dimension and the properties of hydrogen embrittlement were analyzed. The results show that the hy- drogen content of samples and the loss of plastic properties increases along with the time of hydrogen charging, but the reduction of area decrease. For the fracture morphology, the fractal dimension decrease with the time of hydrogen charging. Good corresponding linear relationship exists between the fractal dimension and the reduction of area. The fractal dimension can reflect the effects of hydrogen to the materials.