Intergranular stress corrosion crack susceptibility of austenite stainless steel was evaluated through threepoint bending test conducted in high temperature water. The experimental results showed that the frequent and...Intergranular stress corrosion crack susceptibility of austenite stainless steel was evaluated through threepoint bending test conducted in high temperature water. The experimental results showed that the frequent and efficient introduction of low energy coincidence site lattice boundaries through grain boundary engineering resulted in an apparent improvement of the intergranular stress corrosion crack resistance of austenite stainless steel.展开更多
The feasibility of applying the grain boundary character distribution(GBCD)optimization to Inconel 625 for improving the intergranular corrosion(IGC)resistance was studied.The GBCD was obtained and characterized by el...The feasibility of applying the grain boundary character distribution(GBCD)optimization to Inconel 625 for improving the intergranular corrosion(IGC)resistance was studied.The GBCD was obtained and characterized by electron backscatter diffraction(EBSD)analysis,and its optimization was mainly attributed to annealing twins(Σ3)and twins related to boundaries formed during thermal-mechanical processing(TMP).Through TMP of 5%cold rolling and subsequent annealing at 1150℃for 5 min,the proportion of lowΣcoincidence site lattice(CSL)grain boundaries of the Inconel 625 can be enhanced to about 35.8%which mainly were ofΣ3^(n)(n=1,2,3)type.There is an increase of 24.8%compared with the solution-treated sample,and simultaneously the large-size highly-twinned grain-cluster microstructure is formed.The grain-cluster is mainly composed ofΣ3-Σ3-Σ9 orΣ3-Σ9-Σ27 triple junctions,which is mainly caused by boundary reactions during grain growth.Among them,the IGC resistance ofΣ3 grain boundaries,Σ9 grain boundaries and random grain boundaries is sequentially weakened.With the increase of the lowΣCSL grain boundary fraction,the IGC resistance of Inconel 625 improves.The essential reason is the amount ofΣ3 boundaries interrupting the random boundary network increases and the large grain-cluster arrests the penetration of IGC.展开更多
We have shown that the expression =2tan-1/ derived by Ranganathan to calculate the angles at which there exists a CSL for rotational interfaces in the cubic system can also be applied to general (oblique) two-dimensio...We have shown that the expression =2tan-1/ derived by Ranganathan to calculate the angles at which there exists a CSL for rotational interfaces in the cubic system can also be applied to general (oblique) two-dimensional lattices provided that the quantities 2 and /cos() are rational numbers, with =|b|/|a| and is the angle between the basis vectors a and b. In contrast with Ranganathan’s results, N;given by N=tan2() needs no longer be an integer. Specifically, vectors a and b must have the form a=(1,0);b=(r,tan) where r is an arbitrary rational number. We have also shown that the interfacial classification of cubic twist interfaces based on the recurrence properties of the O-lattice remains valid for arbitrary two-dimensional interfaces provided the above requirements on the lattice are met.展开更多
Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and （111） texture is...Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and （111） texture is the dominate component.As-deposited interconnects undergo the phenomenon of self-annealing at RT,in which some abnormally large grains are found. Lower aspect ratio of lines and anneal treatment procured larger grains and stronger （111） texture. Meanwhile, the intensity proportion of other textures with lower strain energy to （111） texture is decreased. As-deposited specimens reveal （111）（112？ and （111） （231） components, （111） （110） component appeared and （111） （112？ and （111） （231） components were developed during the annealing process. High angle boundaries are dominant in all specimens, boundaries with a misorientation of 55°-60° and ∑3 ones in higher proportion, followed by lower boundaries with a misorientation of 35°-40° and 29 boundaries. As the aspect ratio of lines and anneal treatment increase,there is a gradual in- crement in ∑3 boundaries and a decrease in ∑9 boundaries.展开更多
对七道次异步叠轧铜板采用220℃×30 m in和220℃×40 m in两种工艺进行退火,运用背散射电子衍射技术对两种铜板的再结晶程度、织构和晶界特征分布进行了研究。结果表明,经220℃×40 m in退火处理后,铜板的再结晶较完全,其...对七道次异步叠轧铜板采用220℃×30 m in和220℃×40 m in两种工艺进行退火,运用背散射电子衍射技术对两种铜板的再结晶程度、织构和晶界特征分布进行了研究。结果表明,经220℃×40 m in退火处理后,铜板的再结晶较完全,其织构为明显的{100}〈001〉立方织构;而经220℃×30 m in退火处理后,铜板内仍存在晶体缺陷,其织构为{123}〈412〉轧制织构及少量的{100}〈001〉立方织构。晶界特征分布图表明晶界都主要分布在Σ1、Σ3、Σ7、Σ9和Σ11位置上,采用220℃×40 m in退火处理后铜板中各主要晶界的含量明显高于采用220℃×30m in退火后的。展开更多
利用背散射电子衍射花样(EBSD),分析了冷轧变形量、退火温度和保温时间对高纯铝晶界特征分布的影响,并探讨了纯铝的变形再结晶行为与低∑重位点阵晶界(Coincidence Site Lattice,简称CSL)大量形成之间的内在联系。结果表明,变形量20%的...利用背散射电子衍射花样(EBSD),分析了冷轧变形量、退火温度和保温时间对高纯铝晶界特征分布的影响,并探讨了纯铝的变形再结晶行为与低∑重位点阵晶界(Coincidence Site Lattice,简称CSL)大量形成之间的内在联系。结果表明,变形量20%的试样在360℃退火时低∑-CSL晶界比例达到了44.2%,与低层错能金属相比,铝的∑3n晶界比例较低,其他低∑-CSL晶界比例较高。不同变形量试样的∑3n晶界比例在再结晶温度退火取得最大值,升高退火温度或延长保温时间,晶粒都将发生长大,一般大角度晶界的迁移会吞并已有的低∑-CSL晶界,造成∑3n晶界和低∑-CSL晶界比例都有所下降。展开更多
文摘Intergranular stress corrosion crack susceptibility of austenite stainless steel was evaluated through threepoint bending test conducted in high temperature water. The experimental results showed that the frequent and efficient introduction of low energy coincidence site lattice boundaries through grain boundary engineering resulted in an apparent improvement of the intergranular stress corrosion crack resistance of austenite stainless steel.
基金Funded in part by the National Key Research and Development Program of China(No.2017YFA07007003)the National Natural Science Foundation of China(No.51661019)+1 种基金the Major Projects of Science and Technology in Gansu Province(No.145RTSA004)the Hongliu First-class Discipline Construction Plan of Lanzhou University of Technology。
文摘The feasibility of applying the grain boundary character distribution(GBCD)optimization to Inconel 625 for improving the intergranular corrosion(IGC)resistance was studied.The GBCD was obtained and characterized by electron backscatter diffraction(EBSD)analysis,and its optimization was mainly attributed to annealing twins(Σ3)and twins related to boundaries formed during thermal-mechanical processing(TMP).Through TMP of 5%cold rolling and subsequent annealing at 1150℃for 5 min,the proportion of lowΣcoincidence site lattice(CSL)grain boundaries of the Inconel 625 can be enhanced to about 35.8%which mainly were ofΣ3^(n)(n=1,2,3)type.There is an increase of 24.8%compared with the solution-treated sample,and simultaneously the large-size highly-twinned grain-cluster microstructure is formed.The grain-cluster is mainly composed ofΣ3-Σ3-Σ9 orΣ3-Σ9-Σ27 triple junctions,which is mainly caused by boundary reactions during grain growth.Among them,the IGC resistance ofΣ3 grain boundaries,Σ9 grain boundaries and random grain boundaries is sequentially weakened.With the increase of the lowΣCSL grain boundary fraction,the IGC resistance of Inconel 625 improves.The essential reason is the amount ofΣ3 boundaries interrupting the random boundary network increases and the large grain-cluster arrests the penetration of IGC.
文摘We have shown that the expression =2tan-1/ derived by Ranganathan to calculate the angles at which there exists a CSL for rotational interfaces in the cubic system can also be applied to general (oblique) two-dimensional lattices provided that the quantities 2 and /cos() are rational numbers, with =|b|/|a| and is the angle between the basis vectors a and b. In contrast with Ranganathan’s results, N;given by N=tan2() needs no longer be an integer. Specifically, vectors a and b must have the form a=(1,0);b=(r,tan) where r is an arbitrary rational number. We have also shown that the interfacial classification of cubic twist interfaces based on the recurrence properties of the O-lattice remains valid for arbitrary two-dimensional interfaces provided the above requirements on the lattice are met.
文摘Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and （111） texture is the dominate component.As-deposited interconnects undergo the phenomenon of self-annealing at RT,in which some abnormally large grains are found. Lower aspect ratio of lines and anneal treatment procured larger grains and stronger （111） texture. Meanwhile, the intensity proportion of other textures with lower strain energy to （111） texture is decreased. As-deposited specimens reveal （111）（112？ and （111） （231） components, （111） （110） component appeared and （111） （112？ and （111） （231） components were developed during the annealing process. High angle boundaries are dominant in all specimens, boundaries with a misorientation of 55°-60° and ∑3 ones in higher proportion, followed by lower boundaries with a misorientation of 35°-40° and 29 boundaries. As the aspect ratio of lines and anneal treatment increase,there is a gradual in- crement in ∑3 boundaries and a decrease in ∑9 boundaries.
文摘对七道次异步叠轧铜板采用220℃×30 m in和220℃×40 m in两种工艺进行退火,运用背散射电子衍射技术对两种铜板的再结晶程度、织构和晶界特征分布进行了研究。结果表明,经220℃×40 m in退火处理后,铜板的再结晶较完全,其织构为明显的{100}〈001〉立方织构;而经220℃×30 m in退火处理后,铜板内仍存在晶体缺陷,其织构为{123}〈412〉轧制织构及少量的{100}〈001〉立方织构。晶界特征分布图表明晶界都主要分布在Σ1、Σ3、Σ7、Σ9和Σ11位置上,采用220℃×40 m in退火处理后铜板中各主要晶界的含量明显高于采用220℃×30m in退火后的。
文摘利用背散射电子衍射花样(EBSD),分析了冷轧变形量、退火温度和保温时间对高纯铝晶界特征分布的影响,并探讨了纯铝的变形再结晶行为与低∑重位点阵晶界(Coincidence Site Lattice,简称CSL)大量形成之间的内在联系。结果表明,变形量20%的试样在360℃退火时低∑-CSL晶界比例达到了44.2%,与低层错能金属相比,铝的∑3n晶界比例较低,其他低∑-CSL晶界比例较高。不同变形量试样的∑3n晶界比例在再结晶温度退火取得最大值,升高退火温度或延长保温时间,晶粒都将发生长大,一般大角度晶界的迁移会吞并已有的低∑-CSL晶界,造成∑3n晶界和低∑-CSL晶界比例都有所下降。
