母相时效对Cu—Zn—Al记忆合金稳定性的影响

通过正电子湮没和X—射线衍射对Cu—25.0Zn—4.20Al(Wt％)形状记忆合金母相时效后合金的稳定性进行了研究。结果表明,在第一阶段(10分钟以前)有序度的改变是As上升的主要原因,第二阶段(10分钟到25分钟)过饱和空位的钉扎、聚集起主要作用。     

Cu—Zn—Al合金应力诱发贝氏体相变

测定了母相状态的Ｃｕ－Ｚｎ－Ａｌ记忆合金，在恒应力作用下连续加热过程与中温等温过程的变形量。通过对温度－应变特性，时间－应变特性，组织形貌以及Ｘ光结构分析，揭示出了应力，温度及升温速度对应力诱发贝氏体相变的影响。     

Cu—Zn—Al形状记忆合金的成分设计

本文提出了Ｃｕ－Ｚｎ－Ａｌ形状记忆合金成分设计的一种简便方法，其计算结果与实验结果相符合。     

微量Zr对Cu—Zn—Al合金冷变形能力的影响

研究了微量Ｚｒ对Ｃｕ－Ｚｎ－Ａｌ合金再结晶规律和机械性能的影响，结果表明，在该合金中添加０．２４％Ｚｒ再结晶温度升高，晶粒明显细化，但β相的含量也增多，使冷变形能提高不明显。     

关于Cu—Zn—Al贝氏体相变的阶段性——I.TTT图

从理论上证明了相变过程中形成混合产物的可能性。通过测定Ｃｕ－Ｚｎ－Ａｌ合金ＴＴＴ图，讨论了贝氏体相变阶段性并定义了贝氏体相变阶段。     

Ectoine对Cu—Zn型SOD酶热稳定性的影响

研究了Ectoine对Cu-Zn型SOD酶在热处理条件下的保护作用．研究结果表明，Ectoine对经热处理的Cu-Zn型SOD酶有明显的保护作用．0．7mmol／L的Ectoine可使经50、90、100℃处理的Cu-Zn型SOD酶的相对酶活力分别提高25．7％、19．0%、13．2％；0．5mmol／L的Ectoine在60℃下可使酶活提高26．5%；0．3mmol／L的Ectoine在80℃下可使酶活提高22．1％，0．1mmol／L的Ectoine在70℃下可使酶活提高28．6％．Ectoine与脯氨酸、甘油、海藻糖、谷氨酸、甜菜碱，在相同热处理条件下比较，Ectoine对Cu-Zn型SOD酶的热保护作用最为明显，且用量最少．     

Al—Zn—Mg—Cu合金的超塑性变形力学行为

介绍了一种新的超塑性处理工艺,采用简单的预处理工艺结合升温拉伸,可以使合金获得优异的超塑性,轧制形变组织在拉伸过程中发生动态再结晶,形成细晶组织并赋予合金优异的超塑性。     

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.     

Microstructure and shape memory effect of Cu-26.1Zn-4.8Al alloy

The influence of processing parameters on the microstructure and shape memory effect of Cu-26.1Zn-4.8Al alloy was investigated. The treated specimens were characterized by metallography, X-ray diffraction （XRD） and transmission electron microscopy （TEM） to explain the mechanism of shape memory effect in Cu-26.1Zn-4.8Al alloy. The results reveal that the shape memory effect is markedly increased by appropriate quenching and ageing process. XRD shows that γ phase precipitates from martensite when aged at higher temperature and γ precipitates impair the shape memory effect. TEM analysis indicate that the substructure of plate-like martensite consists of twins and stacking faults.     

One-dimensional nano-structure of Cu-Zn-Al alloy

Cu-Zn-Al alloy of one dimensional nano-structure was prepared and the structure of obtained nano-material was characterized by transmission electron microscope (TEM). It was shown that there are non-linear oscillations on the surface of Cu-Zn-Al alloy and the consanguineous connection exists between non-linear oscillation and the growth process of one dimensional nano-structure. The diameter of one dimensional nano-structure is about 40 nm, and the ratio of length to diameter is over 40. Finally, the growth mechanism of one dimensional nano-structure was also studied.     

热循环对Cu－Zn－Al合金双程记忆效应的影响

本文研究了热循环对Ｃｕ－Ｚｎ－Ａｌ形状记忆合金双程记忆效应的影响。结果表明：双程记忆恢复率随着热循环次数的增加而不断衰减。     

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.     

Cu－Zn－Al形状记忆合金的成分设计

本文提出了Ｃｕ－Ｚｎ－Ａｌ形状记忆合金成分设计的一种简便方法，其计算结果与实验结果相符合。     

微量Zr对Cu－Zn－Al合金冷变形能力的影响

研究了微量Ｚｒ对Ｃｕ－Ｚｎ－Ａｌ合金再结晶规律和机械性能的影响．结果表明：在该合金中添加０．２４％Ｚｒ，再结晶温度升高，晶粒明显细化，但β相的含量也增多，使冷变形能力提高不明显．     

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）.     

钽对NiTi形状记忆合金影响的研究

本文研究了钽对ＮｉＴｉ形状记忆合金的马氏体相变特征及Ｘ射线可视性的影响．结果表明,当钽含量从０增加到４ａｔ％时,其相变温度迅速增加,钽含量超过４ａｔ％时,则趋于缓慢;含钽合金可降低ＮｉＴｉ合金相变温度对ＮｉＴｉ相对含量变化的敏感性;钽的加入可改善ＮｉＴｉ双相合金的Ｘ射线可视性．     

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