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Accession Number DE13-1098286
Title Thermally Induced Dynamic Strain Behavior of a Laser Welded Titanium Ring.
Publication Date Oct 2011
Media Count 22p
Personal Author C. F. Chen J. O. Milewski K. J. Hollis
Abstract The dynamic nature of a moving heat source typical to fusion welding create highly localized, complex thermal and mechanical conditions from which the weld morphology evolves ultimately influencing weld performance. The ability to observe and characterize the dynamic weld conditions is complicated by factors such as the speed of the process, the extreme conditions of temperatures, high intensity heat sources, and rapidly changing mechanical conditions. The survivability of sensors in these harsh environments is also complicated by the steep spatial gradients of temperature and strain and the spatial resolution of these measurements. This is particularly true for high energy, rapidly moving heat sources such as those employed for laser welding. Simulation of the effect of moving heat sources for welding using finite element analysis has evolved significantly in the past decade as commercial software products have become available. The complex nature and the limited understanding of the weld parameters, material properties, and boundary conditions, necessitate dynamic weld response data to assist in model calibration and to a degree, model validation. A weld model with sufficient correspondence to real world conditions as compared to measurement can be useful in extending our understanding of process effects to a greater number of locations than could be measured and at locations not easily measured. In this study dynamic thermal and thermally induced strain conditions in a laser welded titanium ring are measured and compared to a weld simulation modeled using SYSWELD. Reasonable agreement is seen in the location, evolution, and rate of hoop and axial strain measured at various locations during welding. Discussion is provided as how these measurements and simulations may be improved. The goal of the work is to better understand the dynamic conditions of temperature and strain that effect of evolution of the weld morphology, the effect of changing process conditions, and the condition of a welded part.
Keywords Boundary conditions
Calibration
Dynamic characteristics
Finite element method
Heat sources
Laser welding
Morphology
Simulation
Spatial resolution
Strains
Temperature effects
Thermal analysis
Titanium
Validation

 
Source Agency Technical Information Center Oak Ridge Tennessee
NTIS Subject Category 41F - Joining
94G - Manufacturing Processes & Materials Handling
71 - Materials Sciences
Corporate Author Los Alamos National Lab., NM.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1411
Contract Number DE-AC52-06NA25396

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