Development of Small Punch Creep Test Rig, Testing and Validation

Power generation components that operating under extreme conditions are susceptible to creep deformation. Such components rely on comprehensive creep data to ensure its integrity, smooth plant operation, and avoid fatal accident due components catastrophic failure. The small punch creep (SPC) test has emerged as a promising alternative to traditional uniaxial creep testing (UCT), offering advantages in terms of the small amount of material required for test sample. This study aims to develop a cost-effective SPC test rig integrated with an existing UCT machine and investigate its reliability in predicting the creep properties. Comparative analysis establishes a robust correlation factor (Ψ=2.5) between SPC and UCT data for Grade 91 steel at 600°C, enabling accurate estimation of creep rupture life across a broad stress spectrum. Fractographic investigations reveal the transition from ductile to brittle fracture as load levels decrease. The successful of SPC rig development and validation not only expands the creep testing toolset but also enables more efficient material characterization, optimized component design, and improved life prediction methodologies.