Within the framework of a phenomenological approach a set of multi-axial creep damage constitutive equations for 0.5Cr0.5Mo0.25V ferritic steel at 590°C is developed in which a new formulation is employed. The deficiency of the previous formulation and the need for improvement became apparent after a critical review of the development of creep damage constitutive equations for 316 stainless steel(1). The need for improvement was further underpinned by a call for modification of the constitutive equations(36). Recently, a specific formulation was proposed and validated(2)-(4). This paper reports the latest developments of the multi-axial creep constitutive equations for 0.5Cr0.5Mo0.25V ferritic steel at 590°C including: 1) the fundamental requirement; 2) formulation; 3) validation; and 4) conclusion. It systematically shows the suitability of this new set of constitutive equations and the incapability of the previous ones. Furthermore, it contributes knowledge to the methodology.
2003 by The Japan Society of Mechanical Engineers