Sinter-hardening of Ni-Mo pre-alloyed powders with tungsten addition

• Autorzy: Dobrzański L. A. , Otręba J. , Actis Grande M. , Rosso M.
• Konferencja: 12th International Scientific Conference CAM3S'2006, 27-30th November 2006, Gliwice-Zakopane
• Języki publikacji: EN

Abstrakty

EN

Purpose: Purpose of this paper was to present the benefits of powder metallurgy technology and development of sinter-hardening process. The mechanical properties, focusing in particular on hardness and wear resistance, of two different carbon levels pre-alloyed steel powders processed with sinter-hardening method, were described. Microstructure characteristic of produced sinter-hardened Ni-Mo steels with increasing amount of tungsten (from 0 to 0.3% wt.) was taken under consideration. Design/methodology/approach: Different compositions have been tested in order to investigate the influence of various tungsten additions into low (0.4%) and high (0.6%) carbon content of pre-alloyed steel powders. Powders, with addition of 0.7% lubricant, were pressed in a 2000 kN hydraulic press. De-waxing process at 550 degrees centigrade for 60 minutes in a fully nitrogen atmosphere was performed before the sintering. Sinering was carried out in vacuum furnace with argon backfilling. The furnace was equipped with a cooling zone to provide accelerated cooling from the sintering temperature. Green compacts were sintered at the temperature 1120 degrees centigrade for 1 hour and rapidly cooled with a rate 2.5 degrees centigrade/s. Findings: The applied sinter-hardening process with achievement of material characterized by good wear resistance. 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: Considering the achieved outcome, it was revealed that chemical composition and applied process of steels preparation, sinter-hardening with the cooling rate 2.5 degree centigrade/s, results in achieving materials with relatively high hardness and significant resistance to abrasion. Anyhow, further research should be performed. Originality/value: Sinter-hardening of Ni-Mo pre-alloyed powders with the addition of different additions of tungsten, 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; stal niskostopowa; obróbka cieplna typu "sinter-hardening"

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 20, nr 1-2
• Strony: 427--430
• Opis fizyczny: Bibliogr. 19 poz., fot., rys., tab.

Twórcy

autor

Dobrzański L. A.

autor

Otręba J.

autor

Actis Grande M.

autor

Rosso M.

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

Bibliografia

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