Fe合金化对Cu36Zr48Ag8Al8非晶合金的组织和力学性能影响

Effect of Fe Element Addition on the Thermal Stability and Mechanical Behavior of (Cu0.36Zr0.48Ag0.08Al0.08)100-xFex Bulk Metallic Glass

摘要:

选择Cu36Zr48Ag8Al8BMG作为基体合金，研究Fe元素合金化对组织和力学性能的影响，分析了相分离非晶结构和纳米晶对合金力学行为的作用机理，并利用维氏硬度计考察了 Fe的掺杂对合金各相的相对硬度、塑性和压痕形貌的影响规律。结果表明，TEM衬度的眀相为富Fe相，暗相为富Cu、Ag相，由于具有不同的模量和硬度的相分离两相结构的存在，非晶合金在外力加载时呈应变硬化，而晶粒尺寸<5 nm的纳米晶起到弥散强化作用，使合金的强度进一步提高。维氏压头作用下使准脆性的非晶合金发生显著的塑性变形，非晶相硬度较高，其维氏压痕的周围形成了少量半圆型剪切带，且在同样的塑性变形量，塑性越好，剪切带的数量较多、间距较小。晶相硬度较低，其压痕周围没有裂纹出现

Abstract:

The effect and mechanism of Fe element addition in Cu36Zr48Ag8Al8 BMG on structure and mechanical properties were investigated. Effects of phase separation structure and nanocrystalline precipitation on mechanical behaviors were analyzed. Vickers hardness tests were used to study the effect of Fe addition on the hardness and shear band features of the BMG. The results show that Fe-enriched and Cu, Ag-enriched amorphous phase are light and dark phase in TEM contrast, respectively. Phase separation structure with different modulus and hardness in the amorphous alloy, leads to strain hardening behavior under loading. And the nanocrystallines smaller than 5 nm form and dispersion further strengthens the amorphous matrix. A few semi-circular shear bands form around Vickers indention of the amorphous phase. And more semi-circular shear bands with a smaller distance form as the indenter presses on the structure with better plasticity. The Vickers hardness of crystalline phase is lower than that of the amorphous phase, and no flaw exist around the indention