Computational weld mechanics (CWM) is used to estimate the likelihood of hot crack nucleation in a weld joint. A hot crack nucleates when the evolution of the local state of stress, strain, temperature and microstructure in the hot cracking temperature region reaches a critical value. The local evolution of state is determined by a high-resolution 3D transient CWM analysis and compared to experimental data characterizing the material resistance for each type of hot cracking. This paper evaluates the susceptibility to ductility dip cracking (DDC) and solidification cracking, separately, for single bead-on-plate welds of nickel-based alloys (FM82 and Inconel 600). An algorithm determines the hot cracking risk based on the temperature, temperature profile, strain increment, and rate of strain in the hot cracking temperature region. The critical values are obtained from the existing experimental data. The objective is to demonstrate that CWM can be used in the design stage to choose weld parameters, such as weld speed, to reduce the risk of hot cracking for a given material, weld joint and weld structure.

Additional Metadata
Keywords Computational weld mechanics, Ductility dip cracking, Finite element, Hot cracking, Nickel, Solidification cracking
Conference 2012 AIST Steel Properties and Applications Conference, Held in Conjunction with the Materials Science and Technology 2012 Conference and Exhibition, MS and T 2012
Citation
Nasser, A. (Ahmed), Asadi, M. (Mahyar), Goldak, J. (John), & Halim, A.O. (2012). Computational weld mechanics of hot crack nucleation in nickel-based welds. Presented at the 2012 AIST Steel Properties and Applications Conference, Held in Conjunction with the Materials Science and Technology 2012 Conference and Exhibition, MS and T 2012.