Hydrogen Internal Friction Peak in Amorphous Zr-Cu-Al-Si Alloys

摘要

The hydrogen internal friction peak (HIFP) in amorphous (a-) Zr_(60)Cu_(40-y)Al_y (y=0, 10), a-Zr_(50)Cu_(50), a-Zr_(40)Cu_(60) and a-Zr_(40)Cu_(50-x)Al_(10)Si_x (x=0, 1, 3) are studied to pursue a high-strength and high-damping performance as well as the underlying process for the HIFP in a-alloys. The tensile strength, sigma_f, of a-Zr_(60)Cu_(30)Al_(10), a-Zr_(40)Cu_(50)Al_(10) and a-Zr_(40)Cu_(49)Al_(10)Si_1 increases from about 1.5 GPa to 2 GPa with increasing hydrogen concentration, C_H, to 20 at percent. One part of a-Zr_(60)Cu_(30)Al_(10), a-Zr_(40)Cu_(50)Al_(10) and a-Zr_(40)Cu_(49)Al_(10)Si_1 specimens show a very high HIFP beyond 3 X 10~(-2) in the as hydrogen charged state, where the hydrogen induced structural relaxation (HISR) proceeds above room temperature. A maximum value of the HIFP, Q_p~(-1) after the HISR shows a moderate increase with increasing C_H, about 1 X 10~(-2) at CR of 10 at percent. The combination of sigma_f and Q_p~(-1) data indicates that a-Zr_(60)Cu_(40)Al_(10)(H), a-Zr_(40)Cu_(50)Al_(10)(H) and a-Zr_(40)Cu_(49)Al_(10)Si_1(H) after the HISR are potential materials with a high-strength and high-damping performance. The peak temperature of the HIFP T_p, at 10 at percent H is 309 K, 270K and 220K with the measurement frequency of about 200Hz for a-Zr_(40)Cu_(49)Al_(10)Si_1, a-Zr_(40)Cu_(50)Al_(10) and a-Zr_(60)Cu_(30)Al_(10), respectively. It is noted that T_p found for a-Zr_(40)Cu_(49)Al_(10)Si_1 shows a breakthrough for an elevation of T_p of the HIFP in a-alloys, and that a composite material composed of these a-alloys can serve a high-damping performance in a wide temperature range or a wide frequency range. For the underlying process of the HIFP the Q_p~(-1) vs. CR data shows a camel's humps like change for a-Zr_(50)Cu_(50) and a-Zr_(40)Cu_(60), suggesting that only one part of hydrogen atoms can contribute to the HIFP. In contrast, Q_p~(-1) shows a monotonous increase with increasing C_H for C_H below 20 at percent for a-Zr_(60)Co_(40-y)Al_y (y = 0, 10) and a-Zr_(40)Cu_(50-x)Al_(10)Si_x (x = 0, 1, 3), suggesting that most of hydrogen atoms are associated with the HIFP in the a-alloys. For the relaxation parameters of the HIFP, values of 1/tau_0 fall in the range expected for a simple relaxation process for a-Zr_(60)Cu_(40-y)Al_y (y = 0,10) and a-Zr_(40)Cu_(50-x)Al_(10)Si_x (x = 0, 1, 3), but are extremely high for a-Zr_(50)Cu_(50) and a-Zr_(40)Cu_(60), where tau_0 denotes the pre-exponential factor of the relaxation time. These results are discussed in the light of the amorphous structures in the a-alloys.