Constitutive Relation for Ambient-Temperature Creep in Hexagonal Close-Packed Metals
Constitutive Relation for Ambient-Temperature Creep in Hexagonal Close-Packed Metals
复制标题
DOI：
10.2320/matertrans.m2009223
复制
发表时间：
2009-12
影响因子：
1.2
通讯作者：
T. Matsunaga;T. Kameyama;Kohei Takahashi;E. Sato
中科院分区：
文献类型：
--
作者：
T. Matsunaga;T. Kameyama;Kohei Takahashi;E. Sato
本文报道了工业纯钛、纯镁和纯锌三种多晶六方密排金属在环境温度附近甚至低于0.2%额定应力的蠕变试验。这些材料在10-9 S-1附近表现出显著的稳态蠕变速率，应力指数约为3.0。在常温附近的Arrhenius曲线表明，位错核扩散的表观活化能Q非常低，约为20kJ/mol，至少是位错核扩散的四分之一。常温蠕变也具有晶粒度效应，其指数为1.0。这些参数表明，常温蠕变是一种新的蠕变机制。材料。
This paper reports creep tests on three kinds of polycrystalline hexagonal close-packed metals, i.e. commercially pure titanium, pure magnesium, and pure zinc, in the vicinity of ambient temperature even below their 0.2% proof stresses. These materials showed significant steady state creep rates around 10 -9 s -1 and had stress exponents of about 3.0. Arrhenius plots in the vicinity of ambient temperature indicate extremely low apparent activation energies, Q, of about 20 kJ/mol, which is at least one-fourth of the Q of dislocation-core diffusion. Ambient-temperature creep also has a grain-size effect with an exponent of 1.0. These parameters indicate that ambient-temperature creep is a new creep deformation mechanism in h.c.p. materials.