Microstructural characteristic and mechanical properties of Ni-Mo-(W) steels

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

Abstrakty

EN

Purpose: Purpose of this paper was to examine the role of tungsten on properties of two different carbon levels pre-alloyed steel powders. Microstructural characteristic and mechanical properties of sinter-hardened Ni-Mo steels with increasing amount of tungsten (from 0 to 0.3% wt.) were taken under consideration. Design/methodology/approach: Powder mixes (Ni-Mo, Ni-Mo-W) 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 samples 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 and pin-on-disk tests were used. Findings: The effect of chemical composition and applied vacuum sintering with rapid cooling 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: According to the powders characteristic, the applied cooling rate seems to be a good compromise for mechanical properties and microstructures, nevertheless further tests should be carried out in order to examine different cooling rates and parameters of tempering process. Originality/value: 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 alloyed steels; sinter-hardening

PL

metalurgia proszków; spiekanie; stale niskostopowe; obróbka typu sinter-hardening

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 347--350
• Opis fizyczny: Bibliogr. 17 poz., rys., tab., wykr.

Twórcy

autor

Dobrzański L. A.

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

autor

Otręba J.

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

autor

Actis Grande M.

• Politecnico di Torino – Alessandria Campus, Viale T. Michel 5- 15100 Alessandria, Italy

autor

Rosso M.

• Politecnico di Torino – Alessandria Campus, Viale T. Michel 5- 15100 Alessandria, Italy

Bibliografia

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