Type 2 Reference Test Block
The GoodBlock NDT Type 2 Reference Test Blocks are used for routine assessment of the performance of both fluorescent and color contrast penetrant facilities and open containers. The reference block consists of a single panel, of which one half has been hard-plated and the other half prepared to achieve areas of specific roughness. The hard-plated side exhibits five star-shaped discontinuities.
This reference block is 6.1" x 2" x 0.1" (155mm x 50mm x 2.5mm) in size. The substrate is stainless steel, coated with a layer of 60 μm-thick nickel.
The nickel layer is plated with a thickness of 0.5 μm to 1.5 μm and a thin layer of hard chromium. Five star-shaped defects with diameters ranging from 0.12" to 0.22" (3.0mm to 5.5mm) have been artificially generated in this layer.
These five defects are evenly placed according to their size. In order to check washability (visual evaluation of excessive penetrant removal), four adjacent areas with dimensions of 0.98" x 1.38" (25mm x 35mm) are set on the artificial defect side of the test panel, with a roughness of Ra = 2.5 μm, Ra = 5 μm, Ra = 10 μm, and Ra = 15 μm.
The smallest defect is located next to the area displaying the minimum roughness.