The Effect of Preheating on Notched Tensile Strength and Impact Toughness of Ti-6Al-6V-2Sn Laser Welds
Resource
Materials Transactions, 52(3), 406-411
Journal
MATERIALS TRANSACTIONS
Pages
406-411
Date Issued
2011
Date
2011
Author(s)
Tsay, Leu-Wen
Jiang, Yun-Chen
Chen, Chun
Abstract
Notched tensile strength (NTS) and impact toughness were determined for Ti-6Al-6V-2Sn laser welds subjected to post-weld heat treatment (PWHT) at distinct temperatures. In this study, the specimens were either preheated at 300°C or maintained at room temperature before laser welding. The preheated weld, associated with a reduced cooling rate, had obviously lower hardness than the non-preheated weld in the as-welded condition. After PWHT at 482°C for 3 h, the preheated weld also exhibited considerably lower hardness than the non-preheated weld. In general, preheating at 300°C could effectively increase the NTS and impact toughness of Ti-6Al-6V-2Sn laser welds. The preheated weld in the as-welded condition had superior NTS to other welds being tested. On the other hand, the welds after PWHT at 704 °C possessed the best resistance to unstable impact fracture, regardless of preheating. Usually, the coarse a + ß structures together with intergranular α were responsible for the high NTS and impact toughness of the weld. ©2011 The Japan Institute of Metals.
Type
journal article