(大連理工大學(xué) 材料科學(xué)與工程學(xué)院，大連 116024)
摘 要: 利用光學(xué)顯微鏡、電子探針分析、透射電子顯微鏡、X射線衍射儀及拉伸實驗等技術(shù)研究Ni、Si元素對Cu-20Fe(質(zhì)量分數(shù)，%)合金的組織及力學(xué)性能的影響。結(jié)果表明：添加Ni和Si元素導(dǎo)致Cu-20Fe合金中α-Fe枝晶發(fā)生明顯的粗化行為。此外，由于合金元素的添加使得γ-Fe和富銅析出相之間的界面能減小，從而使得富銅析出相的形貌發(fā)生顯著變化，即由近球形轉(zhuǎn)變?yōu)榱⒎叫巍Ｏ啾扔谖刺砑雍辖鹪氐亩辖鸲裕砑雍辖鹪刂螅嘟M元合金的強度和塑性均得到提高。多組元合金的屈服強度和伸長率分別為304 MPa和16%。通過理論計算和實驗驗證，確定合金的主要強化機制為固溶強化和析出強化。
關(guān)鍵字: 顯微組織；形貌轉(zhuǎn)變；界面能；強化機制
（School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China）
Abstract:The effects of Ni and Si elements on the microstructure and mechanical properties of Cu-20Fe (mass fraction, %) alloy were studied by optical microscope, electron probe analysis, transmission electron microscope, X-ray diffractometer and tensile experiment. The results show that the addition of Ni and Si elements leads to obvious coarsening behavior of the α-Fe dendrites in the Cu-20Fe alloy. In addition, due to the addition of alloying elements, the interface energy between γ-Fe and the copper-rich precipitation phase is reduced, so that the morphology of the copper-rich precipitation phase has undergone a significant change, that is, it changes from a nearly spherical shape to a cube. Compared with the binary alloy without adding alloying elements, the strength and plasticity of the multi-component alloy are improved after the addition of alloying elements. The yield strength and elongation of the multi-component alloy are 304MPa and 16%, respectively. Through theoretical calculation and experimental verification, it is determined that the main strengthening mechanism of the alloy is solid solution strengthening and precipitation strengthening.
Key words: microstructure; morphology transformation; interface energy; strengthening mechanism
