Influence of cooling rates on properties of pre-alloyed PM materials

• Autorzy: Dobrzański L. A. , Musztyfaga M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The paper focuses on microstructural and mechanical properties of pre-alloyed Astaloy CrL and CrM sintered steels with high addition of carbon. Design/methodology/approach: The main objective of the present work was to establish the effect of cooling rates on the microstructure and properties such as: Charpy impact test, microhardness, wear resistance (disk on disk test) were evaluated depending on chemical composition. Compacts containing low amounts of chromium, molybdenum and high amount of graphite were sintered in a vacuum furnace at 1120şC in vacuum atmosphere and rapidly cooled in nitrogen with two different rates. Then compacts were tempered in vacuum, and cooled in nitrogen. Obtained samples were analysed by light optical microscopy (LOM) for microstructure observation and scanning electron microscopy (SEM) with EDS for chemical composition. Findings: Sinter hardening is a cost-effective process that consists of sintering and heat treatment in one step, so it minimizes the number of processing steps. It is known that the cooling rate following sintering greatly affect material microstructure, which determine the final properties of sinter-hardened materials. The objective was to understand how sintering conditions influence the development of microstructures and thereby control mechanical properties of materials. Practical implications: Changing the amount of graphite element and cooling rates, will affect the amount of ferrite, perlite, martensite and bainite in the microstructure. Further tests should be carried out in order to examine different cooling rates. Originality/value: Sinter-hardening of CrL and CrM pre-alloyed powders with addition of graphite was investigated to study cooling mechanism.

Słowa kluczowe

EN

powder metallurgy; sintering; sinter-hardening

PL

metalurgia proszków; spiekanie; utwardzanie poprzez spiekanie

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2009
• Tom: Vol. 37, nr 1
• Strony: 28--35
• Opis fizyczny: Bibliogr. 21 poz., rys., tabl.

Twórcy

autor

Dobrzański L. A.

autor

Musztyfaga 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 18a, 44-100 Gliwice, Poland,

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