Fe-Mn-Si形状记忆合金的记忆性能分析

铁基形状记忆合金由于具有优良的形状记忆效应、价格低廉以及加工性能好等优点引起了广泛重视。对Fe-Mn-Si形状记忆合金的形状记忆机制、形状记忆效应的影响因素以及应用进行了评述。     

Fe—Mn—Si形状记忆合金的记忆性能分析

铁基形状记忆合金由于具有优良的形状记忆效应、价格低廉以及加工性能好等优点引起了广泛重视。对Fe-Mn-Si形状记忆合金的形状记忆机制、形状记忆效应的影响因素以及应用进行了评述。     

Fe—Mn—Si形状记忆合金的记忆性能分析

铁基形状记忆合金由于具有优良的形状记忆效应、价格低廉以及加工性能好等优点引起了广泛重视。对Fe—Mn—Si形状记忆合金的形状记忆机制、形状记忆效应的影响因素以及应用进行了评述。     

双程形状记忆效应的唯象动力学模型

构造可以用于描述一维结构的形状记忆合金（SMA）的双程形状记忆效应的唯象动力学模型. 该模型基于与形状记忆合金中热弹性相变有关的唯象理论,将应力场和热场下的滞回环曲线视为马氏体相变和马氏体变体重构在宏观层面上的表现. 为了模拟温度诱发的相变,构造非凸自由能函数,使得函数的每个局部平衡对应于相变过程中的一个相. 在外部负载（力或者热）的作用下,可以通过模拟系统状态（应变）在不同平衡态之间的转变,研究温度诱发的相变. 相变动力学的控制方程采用拉格朗日方程,以非线性微分方程来表示. 利用非线性常微分方程描述单程形状记忆效应,通过对不同相变过程的加权组合描述双程形状记忆效应. 开展有关力和热负载下的数值实验,模拟热和应力诱发的相变以及热负载下与单程形状记忆效应和双程形状记忆效应有关的滞回环,模拟马氏体重构所导致的单滞回环以及超弹性效应所引起的双滞回环. 从实验结果可以看出,双程形状记忆效应及超弹性效应均可以被提出的模型成功捕捉,验证了该模型的描述能力.     

形状记忆合金研究的回顾与前瞻

回顾了与形状记忆效应有紧密联系的马氏体相变一百多年来的发展，介绍了在此基础上研制的各种形状记忆合金的优缺点、发展动向、应用和应用前景，详细论述了在９０年代国际上重点研究的铁基形状记忆合金的研究现状，指出了该研究的发展方向。     

TiNi形状记忆合金是医学上的应用

简介形状记忆效应，说明ＴｉＮｉ合金的性能，综述ＴｉＮｉ形状记忆合金在骨科及其他医学方面的实际应用。     

形状记忆合金研究的回顾与前瞻

回顾了与形状记忆效应有紧密联系的马氏体相变一百多年来的发展，介绍了在此基础上研制的各种形状记忆合金的优缺点、发展动向、应用和应用前景，详细论述了在９０年代国际上重点研究的铁基形状记忆合金的研究现状，指出了该研究的发展方向。     

NiTi形状记忆合金薄膜中的相变

NiNi形状记忆合金薄膜是从块体状形状记忆合金中发展起来的一种新型功能薄膜材料 ,它具有不完全类同于块体状形状记忆合金的相变行为与记忆效应 本文综述了薄膜制备条件、化学成份、热处理工艺及循环条件对这种薄膜的组织结构 ,尤其是主体相变行为和脱溶分解行为的影响 .表明上述因素的影响相当复杂 ,适当调整各种条件方可获得好的形状记忆效应     

形状记忆合金保健文胸的开发

利用镍钛合金丝的形状记忆效应,将合金丝以一定的比例织入棉织物后,用该形状记忆织物制作成文胸内衬,或将织物作为罩杯内垫包覆物与具有保健功能的填充材料结合制成文胸罩杯,从而赋予文胸形状记忆的能力和保健功能．对不同结构的形状记忆合金文胸的外观效果进行了分析．并对不同填充材料不同合金丝比例文胸罩杯的透气性和回弹性进行研究．结果表明,与原夹棉内衬相比．形状记忆合金织物具有更好的保形性;与海绵内衬相比,由羊毛＋中空棉或中空棉＋木棉填充的形状记忆文胸透气性更好且弹性回复率接近;镍钛合金丝比例提高．则文胸保形能力提高而透气率下降．     

TiNi形状记忆合金精密脉冲电阻对焊接头的形状恢复率

对TiNi形状记忆合金精密脉冲电阻对焊接头形状恢复率进行了研究。分析了焊接热量、焊接压力、焊后热处理等焊接参数及冷热循环对接头形状恢复率的影响 ,并对接头的显微组织进行了分析 ,得出了获得最佳接头形状记忆效应的条件。     

Effect of chemical component on shape memory effect of Fe-Mn-Si-Ni-C-RE shape memory alloy

Effect of chemical component on shape memory effect (SME) of Fe-Mn-Si-Ni-C-RE shape memory alloys was studied by bent measurement, thermal cycle training, SEM etc. Results of study indicate that the alloys with high Mn content (25%) appeare better SME, especially in lower strain. SME improves evidently when Si is higher content, especially it‘s range firm 3% up to 4%.But brittleness of Fe-Mn-Si-Ni-C-RE alloy increases by increasing the Si content. SME of the alloy is weakening gradually as carbon content increases under small strain (3%). But in the condition of large strain (above 6%), SME of the alloy whose carbon content ranges from 0.1% to 0.12% shows small decreasing range, especially of alloy with the addition of compound RE.     

Fe—Mn—Si基形状记忆合金及其应用

介绍了形状记忆合金的简要发展史,Fe-Mn-Si合金的形状记忆机理以及合金的主要元素组成,各成分的作用,提高记忆的方法,分析了其应用情况和前景。     

Fe－Mn－Si形状记忆合金研究进展

对近年来Ｆｅ－Ｍｎ－Ｓｉ合金形状记忆效应的影响因素及工程应用的研究结果进行了评述，并对Ｍｎ、Ｓｉ元素，母相强化及热－机械训练对记忆效应的影响进行了讨论     

Phase transformation behaviors and shape memory effects of TiNiFeAl shape memory alloys

Measurements of electrical resistivity, X-ray diffraction, and tensile test at room temperature and ?196°C were performed to investigate the effects of Al addition substituting Ni on the phase transformation behaviors, the mechanical properties, and the shape memory effects of Ti50Ni47Fe2Al1 and Ti50Ni46.5Fe2.5Al1 alloys. It is found that 1at% Al addition dramatically decreases the martensitic start transformation temperature and expands the transformation temperature range of R-phase for TiNiFeAl alloys. The results of tensile test indicate that 1at% Al improves the yield strength of Ti50Ni47Fe2Al1 and Ti50Ni46.5Fe2.5Al1 alloys by 40% and 64%, but de- creases the plasticity to 11% and 12% from 26% and 27% respectively. Moreover, excellent shape memory effect of 6.6% and 7.5% were found in Ti50Ni47Fe2Al1 and Ti50Ni46.5Fe2.5Al1 alloys, which results from the stress-induced martensite transformation from the R-phase.     

Damping performance of Cu-Zn-Al shape memory alloys in engineering structures

The stress strain curves of two CuZnAI shape memory alloys which have the martensltic transformation temperatures of 50℃ and-10℃ respectively, were measured by using electronic material tester after treated by different heat-treatment conditions. The results show that the area enclosed by hysteresis loop of the CuZnAI shape memory alloy in martensltic state is much larger than that of the alloy in austenltic state with super-elasticity at room temperature. Therefore, the former has better vibration attenuation effect. After being oil-quenched, waterquenched, and step-quenched, the CuZnAI alloy takes on more stable shape memory effect, better super-plasticlty and superelasticity (pseudoelasticity). A CuZnAI shape memory alloy damper was designed, produced and installedto a 2-layer frame structure. In addition, the vibration experiments were made by dynamic data collecting analysis meter. The velocity of vibration attenuation of frame structure with CuZnAI shape memory alloy damper is much faster than that without it. And with the help of CuZnAI shape memory alloy damper, the attenuation period reduces to 1/10 of the original.     

形状记忆合金的应用

作为一种新型的材料,形状记忆合金在各领域得到了广泛的应用。因其功能特性,可以用于机械、环保;而由于智能特性,正逐渐被广泛地应用于医学和电子领域。主要介绍了形状记忆合金在机械、环保、医学和电子方面的应用。     

形状记忆合金对混凝土梁驱动效应的有限元分析

将常温下为马氏体状态的Ni—Ti形状记忆合金预拉伸到产生塑性变形后，再把其偏心埋置于钢筋混凝土梁中，利用SMA特殊的形状记忆效应，通过加热合金丝使其发生马氏体逆相变从而产生巨大的恢复力来驱动钢筋混凝土梁。本文运用通用有限元计算软件ANSYS进行了建模和分析，结果证明可以利用SMA对混凝土梁施加较大的预应力，提高梁的强度和刚度．从而实现变形的主动控制，     

Cooling rate effects on the structure and transformation behavior of Cu-Zn-Al shape memory alloys

Different fragments of a hot-rolled and homogenized Cu–Zn–Al shape memory alloy（SMA） were subjected to thermal cycling by means of a differential scanning calorimetric（DSC） device. During thermal cycling, heating was performed at the same constant rate of increasing temperature while cooling was carried out at different rates of decreasing temperature. For each cooling rate, the temperature decreased in the same thermal interval. During each cooling stage, an exothermic peak（maximum） was observed on the DSC thermogram. This peak was associated with forward martensitic transformation. The DSC thermograms were analyzed with PROTEUS software： the critical martensitic transformation start（Ms） and finish（Mf） temperatures were determined by means of integral and tangent methods, and the dissipated heat was evaluated by the area between the corresponding maximum plot and a sigmoid baseline. The effects of the increase in cooling rate, assessed from a calorimetric viewpoint, consisted in the augmentation of the exothermic peak and the delay of direct martensitic transformation. The latter had the tendency to move to lower critical transformation temperatures. The martensite plates changed in morphology by becoming more oriented and by an augmenting in surface relief, which corresponded with the increase in cooling rate as observed by scanning electron microscopy（SEM） and atomic force microscopy（AFM）.