Kinetic Investigation of Boronized 34CrAlNi7 Nitriding Steel

Abstract

In this study, kinetic examinations of boronized 34CrAlNi7 Nitriding Steel samples were described. Samples were boronized in indirect heated fluidized bed furnace consists of Ekabor 1™ boronizing agent at 1123, 1223 and 1323 K for 1, 2 and 4 hours. Morphologically and kinetic examinations of borides formed on the surface of steel samples were studied by optical microscope, scanning electron microscope (SEM) and X-Ray diffraction (XRD). Boride layer thicknesses formed on the steel 34CrAlNi7 ranges from 46,6 ± 3,8 to 351,8 ± 15,2 µm. The hardness of the boride layer formed on the steel 34CrAlNi7 varied between 1001 and 2896 kg/mm2 . Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe2B sublayers as a function of boronizing time and temperature. The kinetics of the reaction has been determined with K=Ko exp (- Q/RT) equation. Activation energy (Q) of boronized steel 34CrAlNi7 was determined as 169 kj/mol.