Spinodal分解始发形成调幅组织的强化机制  

STRENTHENING MECHANISM OF MODULATED STRUCTURE INITIATED BY SPINODAL DECOMPOSITION

作　　者：徐祖耀[1] 

机构地区：[1]上海交通大学材料科学与工程学院,上海200240

出　　处：《金属学报》2011年第1期1-6,共6页Acta Metallurgica Sinica

摘　　要：总结了关于spinodal分解形成调幅组织、使合金强化机制的有限文献,发现合金时效后的屈服强度主要依赖于2个沉淀相的成分差(可由点阵常数差△a来表征)造成的应力场,而不依赖于调幅波长和沉淀相的体积分数.但时效过程中,合金的屈服强度与Δa的变化不呈线性关系.本文作者认为这和时效时调幅组织的周期性局部被破坏,使局部产生应力场的改变有关,提出屈服强度公式:σ_c=(MBΔa)/a,其中M包括Taylor因子(或Schmidt因子)和弹性模量项,B表示局部应力场改变(Δa)/a效果的因子,Δa为两沉淀相的点阵常数差,a为点阵常数平均值.此式及B值还待验证和估算.Through reviewing of a limited number of literatures regarding strengthening mechanism of modulated structure initiated by spinodal decomposition, it is found that the yield strength of aged alloy is mainly dependent on stress field built by the composition different between two precipitate phases which can be characterized by difference between lattice parameter△a and is independent on modulate wave length and volume fraction of precipitate phase. However, in the ageing courses, the changes in yield stress and△a did not show a linear relationship. The present author considers that this may be attributed to the local destruction of periodicity of modulated structure, causing change in stress field during ageing and suggests a yield stress equation：σc = MB△a/a,in which M denotes a sum factor including Taylor （or Schmidt） factor and elastic constants, B, a factor represent the response of local stress field changed the function of△a/a△a, the difference between lattice parameters of two precipitate phases and a, the average lattice parameter. This equation and the B value need to be confirmed and estimated.

关 键 词：SPINODAL分解 调幅组织 强化机制 

分 类 号：TF777.1[冶金工程—钢铁冶金]