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61.
Ferdinando Auricchio Lorenza Petrini 《International journal for numerical methods in engineering》2004,61(6):807-836
An always increasing knowledge on material properties as well as a progressively more sophisticated production technology make shape memory alloys (SMA) extremely interesting for the industrial world. At the same time, SMA devices are typically characterized by complex multi‐axial stress states as well as non‐homogeneous and non‐isothermal conditions both in space and time. This aspect suggests the finite element method as a useful tool to help and improve application design and realization. With this aim, we focus on a three‐dimensional macroscopic thermo‐mechanical model able to reproduce the most significant SMA features (Int. J. Numer. Methods Eng. 2002; 55 : 1255–1264), proposing a simple modification of such a model. However, the suggested modification allows the development of a time‐discrete solution algorithm, which is more effective and robust than the one previously discussed in the literature. We verify the computational tool ability to simulate realistic mechanical boundary value problems with prescribed temperature dependence, studying three SMA applications: a spring actuator, a self‐expanding stent, a coupling device for vacuum tightness. The effectiveness of the model to solve thermo‐mechanical coupled problems will be discussed in a forthcoming work. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
62.
63.
以工业偏钛酸、硫酸锌、氨水为主要原料,用直接沉淀法并进行热处理得到钛酸锌粉体,并用XRD对产物成分进行了检测。结果表明,不同的锌钛比对钛酸锌(ZnO-TiO2)体系的成分有较大影响。 相似文献
64.
NetLinx技术的发展,使得跟踪系统发生了划时代的飞跃,在制造业上的应用更加广泛。本文以一间显像管厂为例,详细介绍了跟踪系统在制造业上的应用。 相似文献
65.
A. MONSALVE M. PÁEZ M. TOLEDANO A. ARTIGAS Y. SEPÚLVEDA y N. VALENCIA 《Fatigue & Fracture of Engineering Materials & Structures》2007,30(8):748-758
The S-N-P (stress, number of cycles, failure probability) curves for 2024 T3 and 7075 T7351 aluminium alloys were obtained. Previously, surface treatments of degreasing and different types of anodizing were applied to samples, evaluating the influence of these treatments on the fatigue life of the alloys. The determination of the S-N-P curves was done using Maennig's method. Rotary fatigue was used because this technique produces greater stress on the sample surfaces, the zone in which it is important to evaluate fatigue resistance. Both the transition range and the finite life range were evaluated, calculating the 1, 50 and 99% fracture probability. SEM was performed in order to characterize the fracture micromechanism. The conclusions were that Maennig's method is useful to evaluate fatigue life of these materials in a fast and efficient manner. Moreover, surface treatments produce a decrease in the fatigue life of both alloys, associating this effect with the surface damage produced on each sample during the treatment. 相似文献
66.
No authorship indicated 《Canadian Metallurgical Quarterly》2007,62(5):388
Announces the 2007 recipient of the Gold Medal Award for Life Achievement in the Practice of Psychology: Patricia M. Bricklin. A brief biography, highlighting areas of special focus in Bricklin's work, is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
No authorship indicated 《Canadian Metallurgical Quarterly》2007,62(8):768
Presents the citation, biography, and selected bibliography for Karl G. J?reskog, one of the 2007 recipients of the American Psychological Association's Award for Distinguished Scientific Applications of Psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
No authorship indicated 《Canadian Metallurgical Quarterly》2007,62(8):786
Presents the citation, biography, and selected bibliography for J?rn Diedrichsen, one of the 2007 recipients of the American Psychological Association's Award for Distinguished Scientific Early Career Contributions to Psychology (perception/motor performance). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
No authorship indicated 《Canadian Metallurgical Quarterly》2007,62(8):796
Presents the citation, biography, and selected bibliography for Patrik O. Vuilleumier, one of the 2007 recipients of the American Psychological Association's Award for Distinguished Scientific Early Career Contributions to Psychology (behavioral and cognitive neuroscience). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
No authorship indicated 《Canadian Metallurgical Quarterly》2007,62(8):800
Presents the citation, biography, and selected bibliograpy for Larke Nahme Huang, the 2007 recipient of the American Psychological Association's Award for Distinguished Senior Career Contributions to Psychology in the Public Interest. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献