Choice of the parameters and algorithm for the magnetic hardness testing of thermally treated carbon steels by the method of regression modeling

Three-dimensional distribution of the magnetic field and the flux in locally magnetized two-layer ferromagnetic objects

“…As it follows from the obtained results, the field H p correlates with the calculated field H A ; however, H p can be easily measured with existing devices unlike H A [14,15]. Thus, it is possible to test the depth of the hardened layer by the magnetic field value measured on the surface of a locally magnetized object.…”

“…To define a more appropriate inspection parameter, field intensity H p is measured by a SIMTEST device [14,15]. This field is achieved in the center of the interpolar space (point A) on the surface of two-layer objects after they are magnetized by a U-shaped electromagnet with subsequent magnetization reversal along the descending hysteresis loop branch until reaching a fixed magnetic flux value [16].…”

Analysis of Requirements and the Feasible Limit for Error Reduction in Two-Parameter Magnetic Determination of Steels’ Hardness

“…The value σ F shows how the use of the second parameter x 2 to determine the value of F decreases (if σ F < 1) or increases (if σ F > 1) the SD of the indirect measurement according to equation (3) compared to using only the parameter x 1 . In the notation (7), from (6) we obtain: Figure 1 shows the results of calculating the dependences σ F = σ F (σ 2 ) by formula (8) in the range 0 ≤ σ 2 ≤ 3 for different coefficients R of the correlation between the parameters x 1 and x 2 in the possible range -1 ≤ R ≤ 1 of its change. Figure 2 shows the results of calculating the dependences by σ F = σ F (R) formula (8) at different values in the range of -1 ≤ R ≤ 1.…”

“…To increase the reliability of magnetic structural analysis, a combined use of several magnetic parameters was proposed. Analysis of the theoretical foundations of such methods, experiments, and modeling showed a strong influence of errors in measuring the parameters used in multiparameter regression equations on the reliability of control [6][7][8][9][10]. Nevertheless, multi-parameter models are used to calculate the hardness of HRC steels [11,12].…”

Magnetic and acoustic characteristics of steel 30CrMnSiA after rolling and pressing

“…It is becoming increasingly urgent to developing techniques and devices enabling one measure locally a whole complex of magnetic characteristics, i.е. to perform multiparameter diagnostics [2,3]. However, multiparameter testing and diagnostics, based on measuring both magnetic parameters and characteristics associated with the dynamics of the rearrangement of the domain structure during magnetization reversal, can provide a more reliable determination of residual stresses and the structural-phase state [1,4].…”