形成能力及力學(xué)性能的影響
(1. 東南大學(xué) 材料科學(xué)與工程學(xué)院，江蘇省先進(jìn)金屬材料高技術(shù)研究重點(diǎn)實(shí)驗(yàn)室，南京 211189；
2. 河海大學(xué) 機(jī)電工程學(xué)院，常州213022)
摘 要: 研究微量元素Ag、Ti、Ga、Ni和Sn對(duì)Cu55Zr38Al7銅基塊體金屬玻璃形成能力及力學(xué)性能的影響。結(jié)果表明：添加2%(摩爾分?jǐn)?shù))的Ag、Ti或Ga均可以提高Cu55Zr38Al7合金的玻璃形成能力；用6%的Ag替代Cu，玻璃棒的臨界直徑可從2 mm增加到4 mm；因此，替代化學(xué)性質(zhì)相似的元素或者擴(kuò)大合金系的原子尺寸范圍對(duì)提高玻璃形成能力具有顯著的效果；然而，添加微量元素均不同程度地降低Cu-Zr-Al金屬玻璃的硬度。斷口表面形貌顯示；微量相似元素替代影響基體在壓縮過(guò)程中剪切帶的繁殖；在微量元素替代的偽四元銅基塊體金屬玻璃中，2% Ti 和2%Ag替代可分別獲得最大壓縮強(qiáng)度2 163 MPa和最大壓縮應(yīng)變8.7%。因此，通過(guò)添加微量元素可以調(diào)諧金屬玻璃的玻璃形成能力和力學(xué)性能。
關(guān)鍵字: 塊體金屬玻璃；玻璃形成能力；微合金化；力學(xué)性能
mechanical properties of Cu-Zr-Al bulk metallic glasses
（1. Jiangsu Key Laboratory for Advanced Metallic Materials, School of Materials Science and Engineering,
Southeast University, Nanjing 211189, China;
2. College of Mechanical and Electrical Engineering, Hohai University, Changzhou 213022, China）
Abstract:The effects of minor additions of Ag, Ti, Ga, Ni and Sn on the glass forming ability (GFA) and mechanical properties of Cu55Zr38Al7 bulk metallic glass were investigated. The results show that the GFA of Cu55Zr38Al7 bulk metallic glass is enhanced by 2% (mole fraction) addition of Ag, Ti or Ga. The critical size of the cast metallic glass rod is enlarged from 2 to 4 mm by 6%Ag addition. Obviously, distinct effects on GFA are obtained by the substitution of chemically similar elements or the enlargement of atom dimension extension in the alloying system. However, Vickers hardness of Cu-Zr-Al BMG decreases with each element substitution. The fracture surface demonstrates the minor similar elements substitution contribution to the propagation behaviour of shear bands during the compressive deformation process. The highest compressive fracture strength of 2 163 MPa and the highest compressive strain of 8.7% are obtained in the pseudo-quaternary Cu-based BMGs with 2%Ti and 2%Ag substitution, respectively. Consequently, GFA and mechanical properties of the bulk metallic glasses can be coordinated by minor alloying additions.
Key words: bulk metallic glasses; glass forming ability; micro-alloying (GFA); mechanical properties
