Development of a Temperature-dependant Elastoplastic Constitutive Model for Metals and Alloys

The test characterization of the stress-strain relationship and the fatigue/failure behaviour under combined mechanical-thermal cyclic loadings for pressure vessels in the petrochemical industry is quite expensive and time consuming. An alternative approach is the finite element numerical analysis which requires an accurate and reliable mathematical constitutive model for the metallic materials. In this project, a temperature-dependent elastoplastic material model will be developed. The model is capable of capturing the accumulated ratcheting strain which is vital to the fatigue and failure of pressure vessels under severe mechanical loading and thermal cycles. This investigation will result in more realistic analysis and design tools for more robust pressure vessels as well as more effective improvements in operation and maintenance of existing facilities for extending their service life.

Yunfa Zhang
Faculty Supervisor: 
Dr. Zihui Xia