Solution Treatment on Mechanical Properties and Microstructures of Al-Li-Cu AlloyYu Cheng, Yin Deng Feng*and Yu Xin Xiang
School of Materials Science and Engineering, Central South University, Changsha 410083, China
- *Corresponding Author:
- Yin Deng Feng
School of Materials Science and Engineering
Central South University
Changsha 410083, China
E-mail: [email protected]
Received Date: May 30, 2012; Accepted Date: July 24, 2012; Published Date: July 30, 2012
Citation: Cheng Y, Feng YD, Xiang YX (2012) Solution Treatment on Mechanical Properties and Microstructures of Al-Li-Cu Alloy. J Material Sci Eng 1:106. doi: 10.4172/2169-0022.1000106
Copyright: © 2012 Cheng Y, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The mechanical properties and microstructures of Al-Li-Cu-Mg-Ag alloy after different solution treatments were investigated by means of Optical Microscopy (OM), tensile test, hardness and electrical conductivity tests, Differential Scanning Calorimetry (DSC), Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Results show that the tensile strength and hardness increase firstly and then decrease with elevating solution temperature when the holding time is kept for 30 min, and the maximum strength and hardness are reached when temperature is 520°C. The mechanical properties of alloy also display similar trend, which increase firstly and then decrease with increasing solution time when alloy is treated at 520°C. The tensile strength, hardness and elongation of the alloy solution treated at 520°C/30 min are 566 Mpa(σb),512 Mpa(σ0.2), 148HB and 8.23% (δ), respectively. TEM shows that an amount of T1 (Al2CuLi) phases are finely and dispersedly distributed in Al substrates, which can be an explanation of a mixed fracture mode of transgranular and intergranular delamination cracks observed by SEM.