J. Wang
,
W. Jin
金属学报(英文版)
Phase transformation behavior of Ti50-x/2Ni50-x/2Cux (x=2, 5, 15) alloys was investigated using differential scanning calorimetry (DSC). The results show that Ti50-x/2Ni50-x/2Cux alloys undergo a two-stage martensitic transformation on cooling and transform reversely in one stage on heating when treated at 823K for 5 hours. Heat treatment has no effect on the transformation behavior of Ti49Ni49Cu2 alloy but does influence that of Ti47.5Ni47.5Cu5 alloy and Ti42.5Ni42.5Cu15 alloy. Effect of heat treatment is related with precipitation of CuNiTi phase. The maximum recoverable elongation of Ti49Ni49Cu2 wire is about 6%.
关键词:
microstructure
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null
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null
,
null
Zengqi ZHAO Lab.of Physics
,
Baotou Research Institute of Rare Earth
,
Baotou
,
014010
,
ChinaFeixia CHEN Dazhi YANG Dept.of Mater.Eng.
,
Dalian University of Technology
,
Dalian
,
116024
,
ChinaEr BAO Dept.of Mater.Eng.
,
Yanshan University
,
Qinhuangdao
,
066004
,
China
材料科学技术（英文）
Isothermal aging behaviours of a CuZnAl shape memory alloy have been investigated by means of dilatometry.The length of the specimens during isothermal aging from 190 to 280℃ increases with the aging time at each temperature.The isothermal aging kinetics fits in Avrami equation and the time exponent n decreases with the increase in aging temperature.The apparent activation energy for the isothermal aging process was measured to be 109.0kJ/mol,which is about equal to that of a relaxation internal friction peak at about 200℃ (f≈1 Hz) in the alloy.
关键词:
isothermal aging kinetics
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null
,
null
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null
,
null
QI Min ZHU Min ZHAO Xu YANG Dazhi ** Dept.of Materials Engineering
,
Dalian University of Technology
,
Dalian
,
116023
,
China*** Institute of Metals Research
,
Academia Sinica
,
Shenyang
,
110015
,
China+ To whom correspondence should be addressed
材料科学技术（英文）
The influence of a small amount of α phase in β′ matrix on shape memory effect and superelasticity of CuZnAl shape memory alloy has been studied systematically.It has been found that transformation temperature can be adjusted in a large scale by controlling the amount of α phase, meanwhile,shape memory effect and superelasticity do not decrease obviously when there exists a small amount of α phase.Based on the optical and trans- mission electron microscopy observation,the influ- ence of α phase on shape memory effect and superelasticity has been discussed.
关键词:
αphase
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null
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null
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null
周醒
,
夏元梦
,
蔺海兰
,
王正君
,
肖文强
,
卞军
,
赵新为
复合材料学报
doi:10.13801/j.cnki.fhclxb.20161208.003
采用Hummers法制备了氧化石墨烯(Graphene Oxide,GO),再与经硅烷偶联剂(APTES)偶联改性纳米SiO2所得的产物(nano SiO2-NH2)混合,制备了石墨烯片(Graphene Sheets,GS)接枝纳米SiO2杂化材料(nano SiO2-g-GS).以nano SiO2-g-GS为填料,热塑性聚氨酯(TPU)为基体,通过熔融共混法制备共混型nanoSiO2-g-GS/TPU复合材料,并对填料和复合材料进行测试和表征.拉伸测试显示nano SiO2-g-GS的加入对基体TPU有一定的补强作用,使复合材料定伸应力(300％ 、500％和1 000％)增大.DSC测试显示,与纯TPU相比,nano SiO2-g-GS/TPU复合材料的结晶温度有大幅升高,填料含量为1wt％时,TPU的结晶温度升高了44℃.形状记忆测试结果显示,随nano SiO2-g-GS含量增加,nano SiO2-g-GS/TPU复合材料的形状回复率(Rr)逐渐降低,但形状固定率(Rf)逐渐升高.当nano SiO2-g-GS质量分数为1wt％时,nano SiO2-g-GS/TPU复合材料性能最佳.
关键词:
热塑性聚氨酯
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功能化石墨烯
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复合材料
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形状记忆性能
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熔融共混
张玉芬
,
姜雪
,
武荣兰
,
李伟伟
,
武荻
,
王吉德
材料科学与工程学报
doi:10.14136/j.cnki.issn 1673-2812.2016.05.021
利用表面引发原子转移自由基聚合(SI-ATRP)的方法在多壁碳纳米管(MWNT)表面接枝聚甲基丙烯酸甲酯(PMMA),接枝改性后的多壁碳纳米管通过原位聚合法与形状记忆聚氨酯(SMPU)合成SMPU/MWNT-PMMA复合材料.采用FTIR、SEM、TGA、DMA等方法表征材料的结构与性能,并测试其形状记忆性能.结果表明,随着MWNT-PMMA含量的增大,复合材料的力学性能显著改善,最大拉伸强度达到81.30MPa,玻璃化转变温度(Tg)增大,热稳定性增强,且复合材料具有电热双敏性,循环四次后形状固定率和形状恢复率均在95％以上,具有较好的形状记忆性能.
关键词:
碳纳米管
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聚氨酯
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ATRP
,
形状记忆
姜雪
,
武荣兰
,
张玉芬
,
吴爱宗
,
王吉德
高分子材料科学与工程
doi:10.16865/j.cnki.1000-7555.2016.03.028
通过表面引发原子转移自由基聚合(SI-ATRP)的方法在蒙脱土表面接枝聚甲基丙烯酸甲酯(PMMA),接枝改性后的蒙脱土与聚氨酯原位聚合制备形状记忆聚氨酯复合材料.采用傅里叶变换红外光谱、X射线衍射、扫描电镜、热重分析、动态力学分析等方法表征材料的结构与性能,并测试其形状记忆性能.结果表明,随着改性蒙脱土含量的增大,复合材料的拉伸强度逐渐增大、玻璃化转变温度(Tg)上升,且改性蒙脱土的加入增大了复合材料的热稳定性,复合材料在循环4次后仍具有很好的形状记忆性能.
关键词:
蒙脱土
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表面引发原子转移自由基聚合
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聚氨酯
,
形状记忆
,
复合材料
龚小蕾
,
张晟
高分子材料科学与工程
通过在聚丙烯酰胺网络中引入丹磺酰胺基团,成功合成了具有pH响应能力的形状记忆材料.pH＞5时丹磺酰胺基团间产生的疏水聚集作为形状记忆材料中的可逆相,这种疏水聚集可在pH=2时由丹磺酰胺基团的质子化而消失.聚丙烯酰胺中的固有化学交联点则作为形状记忆聚合物中的固定相.实验表明,这种材料可在pH=5时被固定为暂时形状,这种暂时形状在pH=2时得以回复到初始形状.其回复率及固定率分别可达95.4％和94.6％.
关键词:
形状记忆
,
丹磺酰胺
,
pH响应
