Functional Steel Hardness and Wear Improving on a Basis of Phenomena of Grain Boundaries Phase Transition
Based on the phenomena the grain boundaries first-order phase transition in range 0.55 – 0.86 of metal melting point with formation of two-dimensional liquid was elaborated the technology of coatings by synthesis of nitrides using of gaseous nitrogen. It was studied the steel elements for forcing-lift of diesel after nitriding. The creation of a concentration gradient of summary nitrogen (from 1.9 up to 0.5 % at) in a layer of alloy up to 3 mm from a surface results in forming graded coatings with step changes of properties. The mechanical behavior of new tools with high surface resistance to wear are defined of the combination of high hardness (800-1000 Hv[GPa]) of surface coatings (enriched of a nanosize nitrides) with high impact toughness of transitional to matrix layer. The tools life times improved more then 1.5 – 2.5 times.
Zhengyi Jiang, Shanqing Li, Jianmin Zeng, Xiaoping Liao and Daoguo Yang
Y. A. Minaev "Functional Steel Hardness and Wear Improving on a Basis of Phenomena of Grain Boundaries Phase Transition", Advanced Materials Research, Vols. 189-193, pp. 4438-4441, 2011