| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Innovative Process Design and Processing for Advanced Structural Materials
|
| Presentation Title |
Mechanisms Driving Defect Formation in High Power Laser Welding of Nickel Alloys |
| Author(s) |
Mingze Gao, Barnali Mondal, Todd Palmer, Tarasankar Debroy |
| On-Site Speaker (Planned) |
Mingze Gao |
| Abstract Scope |
High power laser welding produces deep penetrations, which also display unique processing conditions far different from arc welding or low power laser welding and enhance susceptibility to defects. To better understand the mechanisms driving these defects, high power laser welding was conducted on three widely used nickel alloys. Among these alloys, Inconel 690 is most susceptible to keyhole collapse porosity. On the other hand, Inconel 740H displayed higher susceptibility to hot cracking than Inconel 718 while no such defect was found in Inconel 690. Thermodynamic calculations were conducted to investigate the role of alloying elements on solidification path, which also allows for the evaluation of hot cracking susceptibility. A validated heat transfer and fluid flow model for keyhole mode laser welding was employed to capture the spatially variable thermal histories, fluid flow, and solidification conditions. Local variations in these processing conditions were correlated with the occurrence of location dependent defects. |