欢迎登录材料期刊网

材料期刊网

高级检索

  • 论文(1287)
  • 图书()
  • 专利()
  • 新闻()

MECHANISM OF HYDROGEN FACILICATED CLEAVAGE IN TITANUM ALUMINIDE

CHU Wuyang XIAO Jimei University of Science and Technology Beijing , Beijing , ChinaTHOMPSON AW Carnegie Mellon University , U.S.A

金属学报(英文版)

Both hydrogen induced cracking and overload crack initiated at same characteristic distance, r~*,within the plastic zone along the slip line when the plastic zone developed to a critical ex- tent.For the overload crack. K_(IC)=αr~*~(1/2)[σ_F~((n+1)/2n)/σ_(ys)~((1-n)/2n)],σ_F=σ_0+g[2μbσ_(th)/π~2L(1-v)]~(1/2) For the hydrogen induced cracking: K_(IH)=αr~*~(1/2)[σ_F(H)~((n+1)/2n)/σ_(ys)(H)~((1-n)/2n)], σ_F(H)={σ_0(H)+g[2μbσ_(th)(H)/π~2L(1-v)]~(1/2)}/k Hydrogen pomoting the dislocation multiplication and motion would result in σ_0(H)<σ_0, k>1,Therefore,hydrogen promoting the cleavage fracture in titanum aluminide can be due to that hydrogen facilitates the local plastic deformation,which results in σ_F(H)<σ_F and then K_(IH)

关键词: Ti_3Al , null , null

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,University of Science and Technology Beijing,Beijing 100083,China

QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词: stress corrosion cracking , null , null , null

  • 首页
  • 上一页
  • 1
  • 2
  • 3
  • 4
  • 5
  • 下一页
  • 末页
  • 共129页
  • 跳转 Go

出版年份

刊物分类

相关作者

相关热词