Regular Article

Characterization and boriding kinetics of AISI T1 steel

¹ Universidad Autónoma del Estado de Hidalgo, Escuela Superior de Ciudad Sahagún-Ingeniería Mecánica, Carretera Cd. Sahagún-O tumba s/n, Zona Industrial, C.P. 43990, Hidalgo, México
² Laboratoire de Technologie des Matériaux, Faculté de Génie Mécanique et Génie des Procédés, USTHB, B.P. No. 32, El-Alia, 16111, Bab-Ezzouar, Algiers, Algeria
³ Tecnológico de Monterrey-Campus Santa Fe, Av. Carlos Lazo No. 100, Del. Álvaro Obregón, C.P. 01389, México City, México
⁴ Centro de Investigaciones en Materiales y Metalurgia, Universidad Autónoma del Estado de Hidalgo, Ciudad Universitaria Pachuca-Tulancingo km 4.5, Pachuca, Hidalgo, México
⁵ Universidad Iberoamericana Ciudad de México, Departamento de Física y Matemáticas, Prolongación Paseo de la Reforma 880, Lomas de Santa Fe, C.P. 01219, México City, México

^* e-mail: keddam@yahoo.fr

Received: 11 October 2017
Accepted: 9 August 2018

Abstract

The AISI T1 steel was hardened by the solid boriding process in the temperature range 1123–1273 K for a time duration of 2 to 8 h. A kinetic model, based on the integral method, was applied to the growth of a single boride layer (Fe₂B) at the surface of AISI T1 steel. This diffusion model has been validated experimentally by considering two additional boriding conditions. A numerical solution was then obtained after solving the set of differential algebraic equations in order to compare the experimental thicknesses of Fe₂B layers with the predicted values. The activation energy for boron diffusion in AISI T1 steel was estimated as 212.76 kJ mol⁻¹ and a comparison was made with other values available in the literature. The formed boride layers with a saw-tooth morphology were examined by scanning electron microscopy (SEM). X-ray diffraction confirmed that the borided layer was composed of only Fe₂B. The Daimler-Benz Rockwell-C indentation technique was employed to assess the cohesion of Fe₂B layers on AISI T1 steel. In addition, the pin-on-disc and wear scratch tests were carried out for investigating the wear behaviour of borided AISI T1 steel.