| 摘要 |
1. A test body comprising hairline cracks, for testing the indicating sensitivity of a penetrating test medium, characterised in that the test body consists of an austenitic steel plate (1) on which, so as to form visible boundaries (12, 14), adjacently disposed layers of nickel (2, 4, 6) of differing but exactly determined thickness are applied and in that there are in the nickel layers cracks formed by elastic deformation of the coated test body. |
