The study of mechanical properties and wear behaviour of surface borided dual-phase steel

In this study, the microstructure and mechanical properties and wear behaviour of surface borided dual-phase steel were investigated. For this purpose, specimens made from SAE/AISI1010 steel were categorised into 4 different groups. The specimens in the first group were in as received form and did not receive any heat treatment for boriding. The second group having pearlite and ferrite microstructure was heat treated at 910°C for 120 min to form a continuous layer of boride. The third group of specimens was heat treated at different temperatures between A 1 and A 3 temperatures of Fe-Fe 3 C phase diagram in order to obtain dual-phase microstructure. The specimens in the fourth group were borided at 910°C for 120 min and then the samples were subjected to dual-phase heat treatment at different temperatures between A 1 and A 3 temperatures without being removed from the furnace. Microstructural analyses and micro-hardness, tensile and wear tests of all the samples were out following the heat treatments. The average thickness of boride layer was approximately 63 μm within the matrix of martensite and ferrite. The boride layer consisted of FeB and Fe 2 B compounds. The micro-hardness of boride layer, ferrite grains and martensite particles on borided dual-phase steel was approximately 1437, 241, and 623 HV 0.05 , respectively. The borided dual-phase steels showed higher tensile and yield strengths and lower total and uniform elongation values, compared to specimens in all other groups. The wear behaviours of borided dual-phase steel were also superior to specimens to other specimens in other groups. Scanning electron microscopy (SEM) attached with an energy dispersive spectroscopy (EDS) analyser was used to characterise the worn surfaces.