姚可夫
,
唐迺泳
,
陈南平
金属学报
在透射电子显微镜下对铁素体-奥氏体双相不锈钢薄膜试样进行了动态拉伸试验,原位观察了裂纹尖端塑性变形过程和位错分布,发现在铁素体相和奥氏体相中,裂尖位错组态有明显差异。在铁素体相中,裂尖无位错区较大,且让错易发生交滑移,在裂纹前端形成较大的塑性区。在奥氏体相中,裂尖无位错区较小,发射的位错在其滑移面内逆塞积。两相中裂尖滑移系的选择都与裂尖Schmid因子有关。但当形变较大时,奥氏体相中裂尖二次滑移系的选择不再为裂尖Schmid因子所支配。
关键词:
裂纹尖端
,
dislocation configuration Schmid factor
,
duplex stainless steel
,
null
何建宏
,
唐祥云
,
陈南平
金属学报
采用电化学渗透方法,测定了氢在(α+γ)双相不锈钢中的扩散渗透曲线。氢的表观扩散系数与奥氏体含量(f_γ)的关系为:D=0.27+0.9/f_γ~2(10~(-10)cm~2/s),初步证明氢在(α+γ)双相不锈钢中主要是通过α相和γ相“串联”扩散,扩散系数D≈D_αD_γ/(f_γ~2D_α+f_α~2D_γ),其中D_α,D_γ分别为氢在α相和γ相中的扩散系数,f_α,f_γ分别为α和γ相的体积分数。
关键词:
氢
,
diffusion
,
duplex stainless steel
P.L.Mao
金属学报(英文版)
The effect of high temperature solution heat treatment on the microstructure and ten-sile property of as-cast 0Cr17Mn14Mo2N duplex stainless steel was investigated.Itwas found that the morphology ofδ-ferrite in the dual phases microstructures changedgradually from dendritic to lamellar and then to spheroidal,and its distribution be-came more uniform under appropriate treatment.When the treat temperature waslower than 1250C,the spheroidial ratio and the homogeneous distribution o fδ-ferriteincrease with increasing temperature,which corresponds to a better tensile property.In addition,when the treat temperature reached 1250~C and above,the microstructureconsists of coarse equiaxial δ-ferrite grains with the needle austenite at its boundaries,which results in a decrease of the tensile properties of the steel.
关键词:
duplex stainless steel
,
null
,
null
C.Leygraf
,
J.Pan
,
M.Femenia
金属学报(英文版)
Electrochem,cal scanning tunneling microscopy and scanning electrochemical microscopy have been used for in situ monitoring of localized corrosion processes of different Duplex stainless steels (DSS) in acidic chloride solutions. The techniques allow imaging of local dissolution events with micrometer resolution, as opposed to conventional electrochemical techniques, which only give an overall view of the corrosion behavior. In addition, combined scanning Kelvin probe force microscopy and magnetic force microscopy were used for mapping the Volta potential variation over the surface of DSSs. A significant difference in Volta potential between the austenite and ferrite phases suggests galvanic interaction between the phases. A compositional gradient appears within 2 micrometers across the phase boundary, as seen with scanning Auger microscopy (SAM). In all, the studies suggest that higher alloyed DSS exhibit a more homogeneous dissolution behavior than lower alloyed DSS, due to higher and more similar corrosion resistance of the two phases, and enhanced resistance of the ferrite/austenite phase boundary regions.
关键词:
duplex stainless steel
,
null
,
null
