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1.
研究运行中渗碳的Incoloy 800H裂解管的显微组织及合金元素的分布, 采用了电子探针定性定量分析微区成分。结果表明,裂解管渗碳后显微组织 发生显著变化,其内壁最高含碳量为3%,内壁基体最低含铬量为4%;渗碳 层厚度超过2mm,管内壁基体和碳化物中Fe,Cr,Ni含量不随渗碳层厚度 变化;基体Cr含量下降大于6%,合金由抗磁性的变为铁磁性的;M23C6型碳 化物转变为M7C3型碳化物时的合金碳含量约为1.5%.  相似文献   

2.
研究了3Cr25Ni12耐热钢的组织结构与性能,并对3Cr25Ni12耐热钢的高温强度、抗氧化性等性能进行了探讨,结果表明,3Cr25Ni12耐热钢的奥氏体基体上有弥散分布的二次碳化物M23C6析出,这是3Cr25Ni12耐热钢具有较高热强性的主要原因之一;奥氏体基体中含有较高的铬合金元素,使其抗氧化性能力得到提高  相似文献   

3.
新型耐海水腐蚀低合金钢10CrCuSiV锈层分析研究报告   总被引:9,自引:0,他引:9  
新型耐海水腐蚀低合金钢10CrCuSiV,在大连海域全浸区挂片试验7a后的腐蚀率为0.23mm/a通过金相,岩相、X射线及扫描电镜、电子能谱等分析,都证明了10CrCuSiV钢的锈层致密,附着牢固,粘附性系数小,内锈层以Fe3O4为主,有良好保护性,而合金元素在蚀坑内的富集有效地抑制了局部腐蚀作用。  相似文献   

4.
用金相试验、X射线衍射物相分析和电子探针分析方法,系统地研究了4种镍基钎料钎焊1Cr18Ni9Ti的钎缝组织特征和相组成及其随热处理时间的变化规律。研究结果表明,用BNi1a和BNi2钎料钎焊(1120℃,10min)的缝宽为0.10mm的钎缝由αNi、Ni5Si2,CrB和Fe4.5Ni18.5B6组成,近缝区扩散层由αFe,γFe和Fe2B组成。用BNi5钎料钎焊(1175℃,10min)的缝宽为0.05mm的钎缝由αNi,Ni5Si2和Ni16Cr6Si7组成。用BNi7钎料钎焊(1050℃,10min)的缝宽为0.05mm的钎缝由αNi,Ni2P和(Fe,Ni)3P组成。  相似文献   

5.
高镍奥氏体球墨铸铁高温性能研究   总被引:2,自引:0,他引:2  
研究了Ni,Cr,Mo,Si,Al和Ce等元素对高镍奥低体球墨铸铁高温性能的影响,并探讨了其影响机理,结果表明,Ni,Cr,Mo能显著地提高高温力学性能、抗氧化性能和抗热冲击性能,Al,Si,Cr和微量稀土Ce能有效地提高抗氧化性能,Cr和Mo于晶界处形成碳化物,高温时阻碍晶界滑移及裂纹扩展。  相似文献   

6.
渗碳不锈钢的开发Oarpenter工艺技术公司为轴承和齿轮应用,开发了一种新的渗碳不锈钢,具有良好的抗腐蚀、耐热和抗疲劳性能。Pyrowear675不锈钢的组成为:Fe-13Cr-5.4Co-2.6Ni-0.8Mo-1.6V-0.4Si-0.07C-...  相似文献   

7.
研究了13Ni5A钢铆钉头部Ni-Cr-B-Si合金激光熔覆层的组织、成分、显微硬度和在酸性介质中的抗腐蚀能力,并进行了实地考验.结果表明,采用激光功率密度为1.3×104W/cm2、扫描速度为5mm/s的辐照工艺,获得了与基体呈冶金结合的无裂纹的熔覆涂层,其组织由Ni-Cr-Fe固溶体、Ni3Si、Cr5B5及WC等相组成,显微硬度高出基体两倍多,并在酸性介质中具有优异的抗蚀性能.激光熔覆处理的铆钉经3700h实际生产考验后.明显优于未经.处理的铆钉.  相似文献   

8.
治岭头金矿矿体主要赋存在中元古界陈蔡群变质岩系和上侏罗统磨石山组火山岩中。成矿元素组合为Au,Ag,Sr,Ti,Co,Sn,Mn,Li,V,Cr,W,Ga,Mn,Ni,Cu,Pb,Zn,Ba,Nb,Fe,S,Si,O等。蚀变带元素地球化学异常显示Au与Ag,Cu,Pb,Zn,Sn,Mn异常有较好的相关性。矿床成矿元素侧向综合分带系列为:Au,Ag,Zn,Cu,Pb,Mo,Sn,Cr,Co,Ni,Mn;成矿元素的地球化学演化为Si,Fe ̄(2+)→Fe ̄(2+),Pb,Zn,Cu,Au,Ag,Mn,Sn→Ca,Si,Cr,Co,Ni,Mn,Au是在约200~300℃时,由大量的黄铁矿和金属硫化物沉淀后络合物解离而停积成矿的。  相似文献   

9.
党参中无机元素的组分分析   总被引:1,自引:0,他引:1  
本文用电感偶合等离子发射光谱,原子吸收光谱分析了常参「Codonopsis Pilosula Nannf」中Fe,Cu,Zn,Mn,Cr,Mg,Ca,Se,Al,P,B,Sr,Hg,Pb,Ba,As,Ce,Be,Ni,Nb,V,Ti,Co,Ge,Mo,Cd,Li,Te,W,Ag,Si,Bi,Sn等33种无机元素的组分含量。  相似文献   

10.
Co—Cr—Ni系激光熔覆合金显微结构的研究   总被引:4,自引:0,他引:4  
激光熔覆Co-Cr-Ni系多元合金的金相、X射线衍射和电镜研究表明,合金的主要组成相为具有FCC点阵的Co基固溶体,其中还溶有Cr,Ni,Fe,W等元素,并存在许多位错和层错;其次是与固溶液组成共晶体的碳化物,主要为具有正交点阵并含有薄片状孪晶的(Cr,Co)7C3和Cr7C3。上述亚稳结构在700℃以下,在一定的应力作用下是稳定的。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

15.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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