Mechanical properties and microstructural characteristic of sinter-hardened steels

• Autorzy: Rosso M. , Dobrzański L. , Otręba J. , Actis Grande M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The main goal of this paper was the examination of the role of W addition on properties of two sinter-hardened alloys with two different carbon levels. Additionally the influence of sinter-hardening process has been evaluated. Microstructural characteristic and mechanical properties of Ni-Mo steels with increasing amount of tungsten (from 0 to 0.3% wt.) were taken under consideration. Design/methodology/approach: Powder mixes have been compacted at 700MPa and sintered in a vacuum furnace with argon backfilling at 1120 °C for 60 minutes. Rapid cooling has been applied with an average cooling rate of 2.5 °C/s. Obtained steels were analyzed by scanning microscopy with energy dispersive spectroscopy (EDS) for phase distribution and mapping and light optical microscopy for observations of the microstructure. Charpy impact test, three-point bending, microhardness, pin-on-disk and disk-on-disk tests were used. Findings: The outcome of implemented vacuum sintering with rapid cooling as well as chemical composition were studied in terms of mechanical properties, focusing in particular on impact energy, hardness and wear resistance. The results achieved after the investigation of Ni-Mo and Ni-Mo-W sinter-hardened steels with low and high carbon content proved that applied process of sintering under vacuum and rapid cooling brought expected outcome. Research limitations/implications: The characteristics of powders and the applied cooling rate were found be a good compromise for mechanical properties and microstructures, though further researches should be carried out in order to examine different cooling rates and parameters of tempering process. Originality/value: The effect of W and/or WC additions to highly alloyed steels is well known. In the work the effect of small additions of W and WC to low alloyed steels, especially in terms of hardenability and wear resistance, was investigated.

Słowa kluczowe

EN

powder metallurgy; sintering; low-alloy steel; sinter-hardening

PL

metalurgia proszków; spiekanie; stal niskostopowa; obróbka cieplna; sinter-hardening

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2009
• Tom: Vol. 35, nr 2
• Strony: 117--124
• Opis fizyczny: Bibliogr. 18 poz.

Twórcy

autor

Rosso M.

autor

Dobrzański L.

autor

Otręba J.

autor

Actis Grande M.

• Division of Materials Processing Technologies, Management and Computer Techniques in Materials Science,Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

Bibliografia

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