Report 1@ Modeling of Weld Residual Stresses and Distortion: Computational Procedures and Applications highlights recent developments in advanced weld modeling procedures. First@ the multi-faceted process physics and mechanics associated with welding are briefly outlined: 1) the effects of fluid flow and heat transport in weld pool@ high-temperature material behavior@ residual stresses and distortions; 2) an engineering perspective for today's industrial applications for residual stress and distortion predictions; 3) a unified weld constitutive model for finite element simulation of welding processes; 4) Residual stress effects on structural integrity; 5) outline of future challenges in modeling weld residual stresses and distortions. Report 2: Fast Thermal Solution Procedure for Analyzing 3D Multi-Pass Welded Structures describes a new transient@ explicit@ and closed-form comprehensive thermal solution procedure (CTSP) for simulating the heat flow process associated with complex welded structures. The solution techniques can be used to analyze multi-pass and curved welds in complex structures with convective heat loss along boundaries. The fast solution procedures are particularly suited for residual stress and distortion prediction in complex structures. The fast solution procedures have been validated with experimental data and used for many industrial applications. A set of selected validations and application examples are summarized in this paper to highlight its unique advantages in analyzing realistic structures@ particularly for residual stress and distortion predictions. Report 3: Finite Element and Experimental Study of Residual Stresses in a Multi-Pass Repair Weld summarizes the study of residual stresses induced in a multi-pass repair weld in a thick section test plate@ a butt-welded base plate restrained by transverse strong back stiffeners. The excavation of the repair weld is formed by machining and hand grinding. The excavation is then welded using a four-layer temper bead technique with 135 repair passes to fill the cavity. A global-to-local computational model captures the overall structural deformation during repair. A local 2-D cross section model is used to capture residual stress details at the mid-section of the repair weld. Experimental measurements on the residual stress distributions taken using center hole drilling@ X-ray diffraction@ and deep hole techniques. Both surface and through-thickness residual stress distributions show good agreement between the predictions and measurements@ particularly in the repair area
BULLETIN 455-2000 history
2000BULLETIN 455-2000 RECENT PROGRESS IN ANALYSIS OF RESIDUAL WELDING STRESSES