Saud Safaa N, Hamzah E, Bakhsheshi-Rad H R, Abubakar T
Faculty of Information Science and Engineering, Management and Science University, 40100 Shah Alam, Malaysia.
Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia.
Scanning. 2017 Jan 11;2017:1789454. doi: 10.1155/2017/1789454. eCollection 2017.
The influence of Ta additions on the microstructure and properties of Cu-Al-Ni shape memory alloys was investigated in this paper. The addition of Ta significantly affects the green and porosity densities; the minimum percentage of porosity was observed with the modified prealloyed Cu-Al-Ni-2.0 wt.% Ta. The phase transformation temperatures were shifted towards the highest values after Ta was added. Based on the damping capacity results, the alloy of Cu-Al-Ni-3.0 wt.% Ta has very high internal friction with the maximum equivalent internal friction value twice as high as that of the prealloyed Cu-Al-Ni SMA. Moreover, the prealloyed Cu-Al-Ni SMAs with the addition of 2.0 wt.% Ta exhibited the highest shape recovery ratio in the first cycle (i.e., 100% recovery), and when the number of cycles is increased, this ratio tends to decrease. On the other hand, the modified alloys with 1.0 and 3.0 wt.% Ta implied a linear increment in the shape recovery ratio with increasing number of cycles. Polarization tests in NaCl solution showed that the corrosion resistance of Cu-Al-Ni-Ta SMA improved with escalating Ta concentration as shown by lower corrosion current densities, higher corrosion potential, and formation of stable passive film.
本文研究了添加钽（Ta）对Cu-Al-Ni形状记忆合金微观结构和性能的影响。钽的添加显著影响了生坯密度和孔隙率；在改性预合金化的Cu-Al-Ni-2.0 wt.% Ta中观察到最低的孔隙率百分比。添加钽后，相变温度向最高值移动。基于阻尼能力结果，Cu-Al-Ni-3.0 wt.% Ta合金具有非常高的内耗，其最大等效内耗值是预合金化Cu-Al-Ni形状记忆合金的两倍。此外，添加2.0 wt.% Ta的预合金化Cu-Al-Ni形状记忆合金在第一个循环中表现出最高的形状恢复率（即100%恢复），并且当循环次数增加时，该比率趋于下降。另一方面，添加1.0 wt.% 和3.0 wt.% Ta的改性合金表明形状恢复率随循环次数增加呈线性增加。在NaCl溶液中的极化测试表明，随着钽浓度的增加，Cu-Al-Ni-Ta形状记忆合金的耐腐蚀性得到改善，表现为更低的腐蚀电流密度、更高的腐蚀电位以及形成稳定的钝化膜。
