A study on the matching of constraint between steam turbine blade and laboratory specimens

The matching of constraint between laboratory specimens and actual cracked structures is a key problem of the accurate structure integrity assessment. Different laboratory specimens and the steam turbine blade with different constraints were selected, the matching of constraint between steam turbine blade and laboratory specimens was investigated. The results shown that the steam turbine blade with 2 c = 50 mm, a/2 c = 0.20 has a matching constraint with single edge-notched bend specimen with a/ W = 0.6 and single edge-notched tensile specimen with a/ W = 0.3. The steam turbine blade with 2 c = 50 mm, a/2 c = 0.25 has a matching constraint with single edge-notched bend specimen with a/ W = 0.7. The steam turbine blade with 2 c = 50 mm, a/2 c = 0.30 has a matching constraint with single edge-notched bend specimen with a/ W = 0.5 and single edge-notched tensile specimen with a/ W = 0.1. The steam turbine blade with 2 c = 50 mm, a/2 c = 0.35 has a matching constraint with single edge-notched bend specimen with a/ W = 0.4, compact tension specimen with a/ W = 0.3 and central-cracked tension specimen with a/ W = 0.7. The steam turbine blade with a = 15 mm, a/2 c = 0.30 has a matching constraint with compact tension specimen with a/ W = 0.7 and single edge-notched tensile specimen with a/ W = 0.5. The steam turbine blade with a = 15 mm, a/2 c = 0.40 has a matching constraint with compact tension specimen with a/ W = 0.4. The steam turbine blade with a = 15 mm, a/2 c = 0.50 has a matching constraint with single edge-notched bend specimen with a/ W = 0.5.

Methodical approach for studying kinetics of short and long fatigue cracks growth for irradiated reactor materials. Part 2. Сonstruction of fatique propagation rate diagram on the basis of test of precracked charpy specimens

The finite element technique has been used for estimating the stress intensity factors (SIF) for short cracks emanating from a notch of single-edge bend specimen (SE(B)) and also weight function for this type of the specimen have been determined. On the basis of the received results the uniform equation for calculations SIF for short and long cracks in a specimen such as SEB (at h/W = 0.3) has been offered. The technique of construction of full kinetic diagrams of growth of the short and long fatigue cracks, initiated from the notch, is developed and approved. Full kinetic diagrams of growth of fatigue cracks (short and long) in steel Х18Н10Т and in weld metal in initial and irradiated (up to 40 dpa) conditions were built.