形状记忆合金的开发应用概述

本文叙述了近期形状记忆合金的开发应用状况。重点介绍了FeMnSi形状记忆合金在制作管接头方面的应用及小型驱动器件用形状记忆合金薄膜的制备。文中还列举了形状记忆合金在其他方面应用的实例。     

新型形状记忆合金的开发研究和工程应用

介绍了近年来新型形状记忆合金研究和发展概况,主要包括 Ni-Ti-Nb 系宽滞后形状记忆合金;Ti-Pt、Ti-Pd 系高温形状记忆合金;Ti-V-Al 和 Ti-Mo-Al 系轻型形状记忆合金以及 Fe-Mn-si-Cr(Ni、Co)铁基形状记忆合金等。     

形状记忆合金的发展

形状记忆合金是一种新型功能材料,因为具有温度感知和驱动性能而得到广泛应用.该文阐述了形状记忆合金的发展、分类以及与形状记忆效应有紧密联系的热弹性马氏体相变的原理,最后介绍了形状记忆合金的应用.     

形状记忆合金及其应用现状

形状记忆合金作为一种典型的新材料,近年来已引起世界许多国家的普遍重视。本文就镍钛形状记忆合金、铜系形状记忆合金、特别是铁基形状记忆合金(钢),近年来在材料学方面的发展现状分别作了概述,并以其在现代科学技术上具体的几个典型应用实例作了介绍。     

德国形状记忆合金的研究与开发

本文综述了德国形状记忆合金的研究与开发现状，重点介绍了近年来在形状记忆合金领域的研究中心和研究重点，评述了形状记忆合金在汽车业、医学界等方面的应用状况，展望了该合金应用方面的发展前景。     

廉价的铁基形状记忆合金

本文主要叙述了有关Fe-Mn-Si系和Fe-Mn-Si-Cr系形状记忆合金方面的情况。综述了铁基形状记忆合金的形状记忆机理,近年来的研制概况,及其应用的现状和前景。并简要叙述了有关Ni-Ti系和Cu-Zn-X系形状记忆合金的特点。     

钛基形状记忆合金研究进展

近年来,新型钛基形状记忆合金成为了金属智能材料研究领域的重点发展方向之一。这类合金一方面可以作为生物医用Ni Ti形状记忆合金的替代材料,从根本上避免Ni离子溶出造成的细胞毒性和致敏性等危害;另一方面可以获得较高的马氏体相变温度,成为航空、航天和能源等领域应用的高温形状记忆合金。钛基形状记忆合金主要包括Ti-Nb基、Ti-Ta基和Ti-Zr基合金体系。Ti-Nb基合金的相变温度范围较宽(180~561 K),最大形状记忆效应和超弹性应变分别为4.0%和5.0%左右。二元Ti-Ta和Ti-Zr合金的马氏体相变温度均高于373 K,是典型的高温形状记忆合金。重点评述了添加合金化元素和热机械处理对Ti-Nb、Ti-Ta和Ti-Zr基形状记忆合金的相变特性、微观结构、力学性能、形状记忆效应、超弹性以及生物相容性等方面的影响,并提出了钛基形状记忆合金的未来发展方向。     

一种钛镍形状记忆合金力学训练方法

本发明涉及形状记忆合金，具体为一种钛镍形状记忆合金力学训练方法。本发明以应力控制或应变控制方式，室温下采用对称拉压加载达到循环饱和应力次数，从而获得马氏体相变温度稳定的钛镍形状记忆合金。本发明使形状记忆合金获得稳定的马氏体相变温度，大大缩短了训练时间，节约能源，降低训练成本，对材料无损伤，适合工业应用。     

重熔镍钛合金的形状记忆效应分析

采用不同的工艺及设备对近等原子比的形状记忆合金进行重熔,获得铸态组织形状记忆合金,对采用不同坩埚所制备出的NiTi合金进行对比分析,采用金属坩埚所得到的形状记忆合金的成分满足医疗器械及外科植入物用NiTi形状记忆合金的成分要求,且具有良好的形状记忆效应。     

钎焊温度对TiNi形状记忆合金性能和组织的影响

TiNi形状记忆合金力学性能和组织对温度变化极为敏感。通过改变加热温度，研究了TiNi形状记忆合金的力学性能和组织变化规律。结果表明：加热温度对TiNi形状记忆合金的抗拉强度和超弹性影响较大。TiNi形状记忆合金力学性能变化存在着两个临界转变温度。温度高于650℃，抗拉强度降低；温度高于200℃，超弹性降低。组织由B19相已部分转变为B2相。     

CuZnAl形状记忆合金划痕行为研究

本文系统地研究了铜锌铝形状记忆合金的划痕磨损行为,测定了马氏体相、母相及热轧状态记忆合金的划痕曲线,并对划痕形貌进行了观察和研究。     

Stress-strain behavior and shape memory effect in powder metallurgy TiNi alloys

The shape memory properties of the TiNi alloy produced by a powder metallurgical method have been evaluated from tensile stress-strain curves. The contamination of the powders during atomization can be suppressed by applying the Plasma Rotating Electrode Process (P-REP), so that the compact made by Hot Isostatic Pressing (HIP) is expected to exhibit the shape memory effect identical to the typical alloy grown from melt. The fracture behavior of the P/M alloy is also studied, and the improvement of fracture strength of the P/M alloy is attempted.     

燃烧合成TiNi形状记忆合金及其性能

介绍了用燃烧合成技术由元素粉末制备ＴｉＮｉ形状记忆合金的方法及合成产物的性能。获得的ＴｉＮｉ合金锭坏具有单一ＴｉＮｉ相的铸态组织，成分准确，纯度高，为致密态，有良好的冷热加工塑性。最终加工材的力学性能和形状记忆性能与市售同类材料相当甚至更好。     

Effect of thermomechanical treatment on the structure and functional properties of a 45Ti-45Ni-10Nb alloy

The effect of quenching and high-and low-temperature thermomechanical treatments on the structural changes, the martensitic-transformation kinetics, and the functional shape recovery characteristics of a 45Ti-45Ni-10Nb alloy is studied. Electron microprobe and X-ray diffraction analyses are used to determine the structure and phase composition of the alloy and to establish the phase-transformation temperatures up to the appearance of the shape memory effect. The strains inducing the shape memory effect and providing shape recovery at temperatures above room temperature have been found. The maximum reactive stresses have been determined. Based on the studies performed, the conclusion was made that quenching and high-temperature thermomechanical treatment can provide a broad martensitic-transformation hysteresis in the alloy under study and main shape recovery on heating above room temperature. As a result, the alloy can be used as a material for thermomechanical coupling that can be stored at room temperature and is applied to the thermomechanical joint of pipelines on heating above this temperature.     

形状记忆合金应力与应变实验研究

Ni-Ti形状记忆合金由于有特殊的形状记忆效应和良好的机械性能成为受到很大关注的功能材料。尽管Ti-Ni合金已经被研究了很多年,至今,仍然有很多有趣的现象并没有得到很好的认识,尤其Ni-Ti合金在不同温度下的应力应变曲线的因素的研究上还有很多没有解释清楚的问题。为此笔者在文中详细介绍了Ni-Ti形状记忆合金的应力与应变关系实验的准备,实验过程,以及实验结果的获取。并对实验结果进行了分析总结,得出Ni-Ti形状记忆合金在不同应力及应变速度下的特性数据,为形状记忆合金的应用提供了必要的参考。     

Effect of grain size on the observed pseudoelastic behavior of a Cu-Zn-Al shape memory alloy

The shape of stress-strain curves for a pseudoelastic copper-based shape memory alloy (SMA) has been found to depend strongly on the grain size-to-sample thickness ratio (gs/t). Previous investigators have attributed this effect to reduced grain constraint in coarse-grain samples. The present investigation further analyzes the grain constraint effect by modeling shape memory alloy stress-strain curves. The model results reveal that varying grain constraint can explain the observed grain size effect on stress-strain curves. Furthermore, detailed consideration of the Taylor factor equivalent for Cu-Zn-Al and NiTi shape memory alloys can explain the opposite curvature of polycrystal stress-strain curves for these two materials. Finally, several indices of grain constraint are analyzed for the Cu-Zn-Al alloy examined in the present investigation and for similar alloys used in previous studies. This evaluation reveals that both transformation modulus and transformation stress correlate with gs/t, and each can be used as an index of grain constraint.     

Thermoelastic martensite and shape memory effect in B2 Base Ni-Al-Fe alloy with enhanced ductility

A ductile shape memory alloy of the Ni-AI-Fe system has been developed using principles through the control of microstructure. Addition of Fe to the binary Ni-Al shape memory alloy allows the introduction of a ductile face-centered cubic (fcc) phase in an otherwise extremely brittle β phase alloy, leading to an improvement in its ductility while retaining its ability to exhibit shape memory arising from the martensitic transformation of theβ phase to Ll₀ structure. It is shown that the transformation temperature in the ternary Ni-AI-Fe alloy can be easily controlled by the preannealing in the β+ γ region. Experimental results on the effect of different annealing treatments on the microstructures and the shape memory behavior in this alloy are presented and discussed.     

Ti-Mo-Sn形状记忆合金管在微导尿管上的应用

Recently, minimally invasive surgeries using guide-wire, catheter, stent etc. have spread rapidly as the diagnosis and the medical treatment for a cancer, a disease in a circulatory organ etc. Currently, further maneuverability and functionability of those devices are strongly desired in order to be used widely and safely. Although Ti-Ni shape memory alloys have been used in medical devices such orthodontic wire, guide-wire, it has been suspected that Ni is allergenic and carcinogenic to the human body. Thus the development of Ni-free shape memory alloys has been strongly required. Re- cently, several Ni-free beta-titanium alloys such as Ti-Mo-Al, Ti-Mo-Ga, Ti-Nb-Al have been developed as new-type shape memory alloys. We have been studying Ti-Mo based beta-titanium alloys and Ti-Mo-Sn alloy has constantly superelasticity of 3%. The purpose of present study is to propose the micro catheter with thin wall and high flexibility using To-Mo-Sn alloys tube on the basis of its mechanical properties.     

Development and characterization of Nickel–Titanium–Zirconium shape memory alloy for engineering applications

Shape Memory Alloys (SMA) are unique class of alloys which possess various engineering applications. One such SMA is Nickel–Titanium (Nitinol) shape memory alloy. The problem, however with Nickel is that the metal may leach out in form of toxic Ni²⁺ ions. The latter may prove costly when used in various applications. To increase the corrosion resistant properties of Nitinol and to evaluate its shape memory properties, small amount of Zirconium i.e. 5 and 10 at % are added into the existing Nitinol system. Buttons of Nitinol and Nickel–Titanium with Zirconium additions are made using the button arc furnace. For the characterization of the alloys, various techniques including Energy Dispersive Spectroscopy (EDS), Back Scattering Electron (BSE) imaging, Differential Scanning Calorimetry (DSC) have been performed. The work conducted reveals that addition of Zirconium in Nitinol has marked influence on microstructure, shape memory properties, transformation temperature, hardness values, and corrosion properties of the alloy.