从韧性断口分形理论出发，导出了延伸率公式δ＝ｋｒｓＢｌ－１ρ－１／２（Ｗ／ｄ）２ＤＦ－２其中ＤＦ是分形维数，ｋ是常数，ｒｓ是表面能，ｌ，Ｗ和Ｂ是试样尺寸，ｄ是晶粒尺寸，ρ是夹杂面密度．３１０不锈钢充氢后δ和ＤＦ均下降，且氢量愈高，δ和ＤＦ均愈小．实验表明，δ随ＤＦ的降低而指数下降．上式指出，δ随ｄ和ρ的减小而增大，随长度ｌ降低及宽度Ｗ和厚度Ｂ的增大而增大，这些均和一般的实验结果相符合．
Based on a fractal model for ductile fracture,a theoretical formula of elongation to failure is established,i.e.,whereδstands for elongation,k for a constant,rs for surface energy,B,l and W for thickness,length and width of the specimen,respectively,ρ for area density of inclusions,d for average grain size and DF for the fractal dimension of the fracture surface.Bothδand DF for precharged 310 austenitic stainless steel decreased with the increase of charging time.Experiment showed that lnδ decreased linearly with the decrease of DF,which is consistent with above-mentioned formula.On the other hand, the formula also shows that the smallar the d,ρ and l,and the larger the W and B, the larger theδ,which conforms to the experimental results.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] | |
| [8] | DauskarktRH,HaubensakF,RitchieO．ActaMetall．,1990 |
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