Abstract
The influence of elements in steel on anode plasma electrolytic boriding has been studied. The modified layers and surfaces on steel samples were analyzed by a scanning electron microscope, an X-ray diffractometer, a surface profiler, a microhardness tester, and a ball-disc tribometer. With 1045 steel as the control group, the same treatment parameters (treatment with 5 min, 200 V of voltage, 5% boric acid, and 10% ammonium chloride) were implemented on various steel substrates. It was found that a low content of carbon would hinder the penetration of boron, and other metallic elements can improve the mircrohardness gradient and decrease the wear-rate. Chromium and manganese can increase the maximum microhardness than treated 1045 by about 15%, but have a detrimental effect on surface flatness. Nevertheless, manganese has the ability to rapidly create a layer of oxide that enhances the tribological characteristics, leading to a remarkably low average friction coefficient of 0.26 for 1046 steel. The presence of molybdenum in the element composition of 4140 steel results in a notable enhancement of surface properties, namely in terms of wear resistance, with a minimum wear-rate 2.1 × 10−6 g/Nm for 4140 steel. Nickel does not appear to have a notable impact on the surface characteristics of the modified samples.
