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1.
形状记忆合金的应用不断扩大作为传感器和致动器使用的形状记忆合金,要求加热和冷却时的温度滞后小、反复工作性能优良等特性,可以使用通过母R相(即菱面体相,是马氏体氏相的一种类型)转变而回复原形的Ni-Ti二元合金或利用母相马氏体相斜方晶结构)转变的Ni-...  相似文献   

2.
探讨了热处理和热循环对空心阴极离子镀(ACD)法在玻璃基板上制备的Nij-49.12%Ti形状记忆合金薄膜的影响。结果表明,由于镀膜时基板 温度较高,所得的膜已部分晶化,其组织为母相组织。经热处理后,其组织发生一系列变化。随加热温度的升高和保温时间的延长,其晶化程度变好,并伴随产生R相、马氏体相和Ni3Ti,同时其相变温度也随之有所提高,但是当加热温度过高和保温时间过长,样品中各相的量减少,其衍射强度降低。薄膜经热循环后,其相应温度也发生变化。随着热循环次数增加,As和Af点逐渐升高,Ms点有所降低,tR基本保持不变。还发现薄膜经热处理后,其表面晶化程度不及内层。  相似文献   

3.
通过低温(-70℃)拉伸制备不同马氏体相变量1Cr18Ni9Ti试样,用XRD,TEM及金相观察研究形变诱发马氏体相变的规律。用电化学方法研究α马氏体(铁磁相)含量对1Cr18Ni9Ti钢在含Cl^-溶液中孔蚀敏感性的影响,结果表明,随试样变形量加大,形变诱发马氏体中铁磁性的α马氏体含量不断增大,而ε马氏体相的量始终较小。材料的孔蚀敏感性失随铁磁相含量的增大而增大,当铁磁相含量达到4.58%以后,  相似文献   

4.
用X射线衍射、扫描电镜和电子探针微区分析等方法,对含Fe和Zr的NiTi合金的相关系进行了研究。结果表明:在室温下,合金中的相组织由三种相变形成。Zr对预马氏体R相相变有抑制作用,而对平衡共析分解的形成则有促进作用。Fe对这两种相变的作用与Zr相反。经高温长时间保温处理,加zr合金的析出相为Ni_3Ti_2,而加Fe的合金,析出相为Ni_4Ti_3。合金中出现的相也随基体的初始成份不同而有所变化。  相似文献   

5.
通过低温(-70℃)拉伸制备不同马氏体相交量的1Cr18Ni9Ti试样,用XRD、TEM及金相观察研究形变诱发马氏体相变的规律。用电化学方法研究。α’马氏体(铁磁相)含量对1Cr18Ni9Ti钢在含Cl-溶液中孔蚀敏感性的影响。结果表明:随试样变形量加大,形变诱发马氏体中铁磁性的α’马氏体含量不断增大,而ε马氏体相的量始终较小。材料的孔蚀敏感性先随铁磁相含量的增大而增大;当铁磁相含量达到4.58%以后,孔蚀敏感性反而渐降;当铁磁相含量超过25.5%后,孔蚀敏感性又增加。  相似文献   

6.
TiNi形状记忆合金薄膜的位借与相变   总被引:2,自引:1,他引:1  
用X射线衍射线形的傅里叶分析及电阻法,研究了溅射Ti-49.37at%Ni合金薄膜的位错组态及相转变温度随退火条件的变化规律,以及位错密度与相变温度的关系。研究结果表明:随退火温度升高和保温时间增加,平均位错密度下降,马氏体相变温度升高。位错密度的变化受析出相粒子的大小和分布制约。随位错密度增加,马氏体相变温度下降,R相变温度基本保持不变。  相似文献   

7.
TiNi形状记忆合金薄膜的位错与相变   总被引:1,自引:0,他引:1  
用X射线衍射线形的傅里叶分析及电阻法,研究了溅射Ti-49.37at%Ni合金薄膜的位错组态及相转变温度随退火条件的变化规律,以及位错密度与相位温度的关系。研究结构表明:随退火温度升高和保温时间增加,平均位错密度下降,马氏体相变温度升高,位错密度的变化受析出相粒子的大小和分布制约。随位错密度增加,马氏体相变温度下降,R相变温度基本保持不变。  相似文献   

8.
微型机械用Ni┐Ti形状记忆合金薄膜的新热处理法微型机械日益广泛地用于医学、生物学、半导体产业等许多科技和工业领域中,发挥了重要作用。Ni-Ti形状记忆合金薄膜用于制作微型致动器是一种不可缺少的材料。最近,日本金属材料技术研究所与筑波大学合作开发成功...  相似文献   

9.
Cu基形状记忆合金的时效   总被引:5,自引:2,他引:5  
对比研究了时效对亚共析Cu-12.0Al-5.0Ni-2.0Mn-1.0Ti(wt.-%)合金与Cu-20.0Zn-6.0Al-微量B(wt.-%)合金热稳定性的影响。结果表明,无论在母相状态或马氏体相状态,Cu-Al-Ni合金的时效热稳定性均远优于Cu-Zn-Al合金。Cu-Al-Ni合金母相状态时效伴随着DO_3有序畴长大,基体中Al、Ni、Mn等元素贫化,导致M_s点升高,马氏体转变量降低。Cu-Zn-Al合金母相状态时效伴随贝氏体转变,引起基体富Zn富Al,导致M_s点下降,马氏体量降低。Cu-Al-Ni合金高的时效热稳定性可能来源于Ni对Al、Cu等原子扩散的阻碍作用。  相似文献   

10.
研究了(Ti0.7Zr0.2V0.1)Ni合金的相结构和电化学性能,结果表明:在比较快的冷却条件下,合金铸态组织为具有B2结构的单一奥氏体相;充氢使唤结构和奥氏体相转变为单斜结构的马氏体相;反复电以放氢使Ti2Ni2和Zr9Ni相逐渐从母中析出。  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 rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.  相似文献   

14.
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   

15.
《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   

16.
《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   

17.
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   

18.
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   

19.
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   

20.
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   

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