IIW2 test block (V-2 test block) is a standard test block passed by the International Welding Society. V-2 (DIN54122) and IIW test blocks, the advantages of V-2 test blocks are light weight and easy to carry, especially suitable for use in the field.
Key points of use:
1) Measure the incident point and the sensitivity of the probe by using a circular reflector with a radius of R50mm
2) Using reflective Φ5 hole surface, the range of refraction angle is 45° to 65° and 65° to 75° respectively.
3) Using multiple longitudinal wave reflections with a surface thickness of 12.5mm, horizontal line and vertical line detectors can be determined
4) Use two arcs, R25 and R50, time axis and zero point correction.
Material: 20 (45) forged steel forging blank printing normalizing heat treatment.
Inspection items: test requirements for measurement.
The chemical composition of the body material, the main chemical composition should comply with GB699 (high-quality carbon structural steel steel grade and general technical conditions) (sampling).
Body material: The bulk material size is normalized, the size is 5-6, and the hardness is 250+25HB (sampling).
Material internal defects: When inspecting the blank, the 8dB signal in the axial and radial directions of the blank is smaller than the diameter of the 2mm hole.
Acoustic characteristics: Try to shield the detection surface and the straight probe, and the surface to be tested at frequencies above 2.5MHz shall not have defect echoes greater than the detection distance, and the echo amplitude of the 2mm flat-bottomed hole on the 20mm plane is 1/4.
Appearance: The surface must not have obvious scratches, bumps, rust and other defects. Surface roughness Ra1.6: the detection surface, and the rest Ra6.3.