Effect of tool microstructure on the white layer formation

• Autorzy: Krawczyk J. , Pacyna J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Purpose of this paper: This work supplements the knowledge concerning formation of the white layer on the surface of the tools being utilized in high temperature metal forming processes. Eight iron-based materials were tested: 3 ledeburitic cast steels, 2 hypereutectoid cast steels, normalized and stress relief annealed steel, hardened and tempered steel and nodular mottled cast iron. Design/methodology/approach: The exploitation tests were performed on the hot rolling mills for selected rolled sections, rolling stands and roll passes. The samples were cut out of the roll in such a way that they contained the roll working surface and were used for metallographic observations of the subsurface zone. Findings: It was found, that uniform distribution of dispersed precipitates of hypereutectoid cementite in the alloy matrix prevents the formation of the white layer on the surface of the rolls. Research limitations/implications: The white layer definition was given. An influence of the microstructure of iron base alloys on the susceptibility to form the white layer on their surface due to tribological contact was also determined. Practical implications: The procedure for obtaining rolled products of better quality as well as for restricting the probability of roll cracking was proposed. Obtained results should allow proper design of the microstructure of the materials for tools. Originality/value: This work contains several new aspects, which are: the unique tribological conditions for performing the tests, wide range of investigated materials, and combining the microstructure of the material with the susceptibility of the formation of the white layer on its surface. The results of this research may be used by the producers of tools for high temperature metal forming.

Słowa kluczowe

EN

tool materials; mill rolls; high temperature tribology; white layer

PL

materiały narzędziowe; walce hutnicze; tribologia wysokich temperatur; warstwa biała

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 17, nr 1-2
• Strony: 93--96
• Opis fizyczny: Bibliogr. 15 poz., rys., tab.

Twórcy

autor

Krawczyk J.

• Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland

autor

Pacyna J.

• Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland

Bibliografia

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• [15] J. Pacyna, J. Krawczyk, The influence of heat treatment on transformed ledeburite morphology in hypoeutectic alloys, 10th Jubilee International Scientific Conference Achievements in Mechanical & Materials Engineering, Gliwice-Kraków-Zakopane, December 9-13, 2001, 429-434 (in Polish).