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1.
熊良钺  陈健  胡壮麒 《金属学报》1996,32(11):1189-1193
测量了塑性金属间化合物合金Ni50Al30Fe20,Ni50Al20Fe30,Ni60Al20Fe20单晶和多晶的正电子寿命谱。基于正电子寿命谱的特征参数引入了正电子双区域捕获模型,并讨论了这些合金微观结构与力学性能之间的关系。  相似文献   

2.
本文研究了在950℃空气中,表面涂Na_2SO_4盐膜的条件下,NiAl,NiAl-20%Fe及渗铝后的高温热腐蚀行为。在热腐蚀过程中,NiAl合金表面能形成Al_2O_3膜,显示出一定的耐蚀性能。但Al_2O_3膜易开裂,Al_2O_3膜的溶解及开裂会引发合金发生快速热腐蚀;20%Fe的加入则使NiAl合金的耐蚀性能显著变差,合金表面不能形成单一的Al_2O_3膜;渗铝处理可以明显提高NiAl-20%Fe合金的耐蚀性能,且渗铝涂层的耐蚀性能优于NiAl合金,这与铝化物涂层中的Al含量较高,Al_2O_3膜的开裂倾向较小有关。  相似文献   

3.
测量了塑性金属间化合物合金Ni(50)Al(30)Fe(20),Ni(50)Al(20)Fe(30)和Ni(60)Al(20)Fe(20)单晶和多晶的正电子寿命谱.基于正电子寿命谱的特征参数引入了正电子双区域捕获模型,并讨论了这些合金微观结构与力学性能之间的关系.  相似文献   

4.
本文研究了在950℃空气中,表面涂Na2SO4盐膜的条件下,NiAl,NiaL-20%Fe及渗铝后的高温热腐蚀行为。在热腐蚀过程中,NiAl合金表面形成AlO3膜,显示出一定的耐蚀性能。但Al2O3膜易开裂,Al2O3膜易开裂,Al2O3膜的溶解开裂会引发合工发生快速热腐蚀,20%Fe的加入则使NiAl合金的耐蚀性能显著变差,合金表面不能形成单一的Al2O3膜;渗铝处理可以明显提高NiAl-20^  相似文献   

5.
Fe3Al金属间化合物的高温抗氧化性能   总被引:12,自引:0,他引:12  
孙杨善  余新泉  黄海波  孙国雄 《金属学报》1998,34(11):1131-1136
当温度超过1000℃时,二元FeAl的抗氧化性能随温度上升而争剧下降,对1200℃氧化试样的SEM分析发现试样表面存在晶须状氧化物,氧化层与基体的界面上有大量的孔洞。微量的Ce加入Fe3Al可显著地改善合金的抗氧化性能,在1200℃长时间氧化后,含Ce的Fe3Al试样表面平整致密,且无氧化物剥落,其抗氧化性能比不含Ce的合金提高了一个数据级。  相似文献   

6.
MCrAlY涂层对TiAl金属间化合物抗高温氧化性能的影响   总被引:8,自引:2,他引:8  
研究了溅射Co-30Cr-6Al-0.5Y及Ni-30Cr-6Al-0.5Y涂层对TiAl金属间化合物抗高温氧化性能的影响。结果表明,在900℃-1000℃范围内,CoCrAlY,NiCrAlY涂层表面由于可形成粘附性良好的Al2O3膜。大大改善了TiAl金属间化合物的抗氧化性能。  相似文献   

7.
阿尔尼科铝铁镍钴系和铁铬钴系永磁合金阿尔尼科合金和铁铬钴永磁合金是目前常用的典型永磁合金。阿尔尼科铝铁镍钴合金以MK钢(Fe—12Al-25Ni)和新型KS钢(Fe—30Co—20Ni-7Al-1Ti)为基础,现已开发出很多种新合金,包括Ainico...  相似文献   

8.
研究了表面涂覆CeO2对Fe-23Cr-5Al合金900℃和1000℃下形成的Al2O3膜生长应力的影响。涂覆CeO2增大了合金的氧化速率,促进了Al2O3膜的起皱同时也增大了Al2O3膜的生长应力。涂覆CeO2表面形成的起皱的Al2O3膜在冷却过程中剥落量较少;而在真空保温过程中应力不容易释放。认为表面涂覆CeO2对Fe-23Cr-5Al的抗氧化并不能起到改善作用。  相似文献   

9.
应用阳极极化及AES/XPS技术,研究了Fe-30.8Mn-8.2Al奥氏体合金在pH值为-0.8至15.3的水溶液中的腐蚀性能,并与Fe-30Mn合金、低碳钢、9%Ni低温钢及1Cr13不锈钢进行对比。在所测试的水溶液中,该合金的腐蚀抗力优于低碳钢和Fe-30Mn合金,与9%Ni钢相当,但不及1Cr13不锈钢。Fe-30.8Mn-8.2Al合金在1mol/LNa2SO个中形成的钝化膜的最表层可能为氢氧化物,而膜的主体由Fe2O3、Mn2O3及Al2O3组成。  相似文献   

10.
李河清 《铸造》1998,(5):29-31
以合金的氧化增重为参照系,结合合金氧化的其它特征,对不同成分的铸造Fe-Cr-Ni-Al耐热合金的氧化膜剥落情况进行了是纳分析,试验结果表明,用氧化剥落速率来评定这种合金的抗氧化性是可行的。  相似文献   

11.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

12.
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.  相似文献   

13.
The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.  相似文献   

14.
《中国铸造》2014,(6):537-538
The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.  相似文献   

15.
《中国铸造》2014,(6):542-546
China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society (FICMES) each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.  相似文献   

16.
正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.  相似文献   

17.
正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis  相似文献   

18.
Preface     
<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of  相似文献   

19.
The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.  相似文献   

20.
The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.  相似文献   

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