| 摘要 |
The invention relates to methods for quality control of the stress-strain conditions of articles made of ferromagnetic and paramagnetic materials. In the first variant, factors K inmean, Kinmin and Kinmax characterising the mean, minimum and maximum levels of residual stresses, respectively and factors g= K inmean/ Kinmax or p= Kinmax/ Kinmin are defined according to the difference of values of magnetic field intensity. The factors Kin mean, g or p are compared with corresponding admissible factors Kin mean, g* or p* obtained for the samples of a nondeffective product, the suitability of a controlled product being evaluated by using said comparison. In the second variant, the gradients of the magnetic field intensity are determined for the controlled product in each measuring channel and therebetween. Using said gradients, a magnetic index mk of the product and the index of the deformation capacity of the product's material dk= 2ROOT mk are determined for each measuring channel and therebetween, said indexes being compared with relevant limit values of mlim and dlim. Results of said comparison are used in order to evaluate the fitness for use of the controlled product and the limit service time thereof. |
