Development of a high temperature material model for grade s275jr steel

The paper presents test results for the mechanical and creep properties of the European steel grade S275JR at high temperatures. The objective of the research was to obtain a reliable estimate of creep strain development in the temperature range 400–600 °C, and to identify the critical thermo-mechanical parameters which activate the creep mechanism. Tests of mechanical properties at temperature levels up to 600 °C have shown good agreement with the reduction factors for yield strength and modulus of elasticity given in Eurocode 3 and other comparable studies. A critical temperature for creep development of approximately 400 °C was identified in the tests. The creep tests conducted have also shown that the creep strain rate starts to develop significantly at temperatures around 500 °C when coupons are exposed to a mid-range stress level equal to 60% of the stress at 0.2% strain. The temperature level of 600 °C is identified as the upper-bound temperature for creep development, since creep develops very rapidly, even at very low stress levels. Finally, the paper presents an analytical creep model suitable for implementation in Finite Element-based numerical models.