Microstructure and properties of vacuum melted high cobalt and cobalt-free maraging steels

• Autorzy: Pawlak S. J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Steel cleanliness, microstructure and fracture mode have been studied, with the aim of enhancing mechanical properties and toughness of the high cobalt and cobalt-free maraging steels. Design/methodology/approach: To fully evaluate all relevant metallurgical factors affecting steel mechanical properties and toughness, broad range of the experimental techniques was used: quantitative metallography, X-ray diffraction, TEM and SEM fractography. Findings: Purity of the laboratory vacuum melted steels was similar to that of foreign industrial steels of the aircraft quality. It was showed that cobalt-free maraging steel could achieve properties comparable to the steel with very high cobalt content. Fracture surface morphologies were highly dependent on the steel grade and type of the mechanical test. In higher strength, the high cobalt steel fractures were generally more flat and more ductile than in the Co-free steel, particularly in the impact test. Research limitations/implications: Further comparative studies of the high cobalt and cobalt-free maraging steels are required on the properties, fracture modes and service properties of a selected parts. Practical implications: Very high mechanical properties and fracture toughness values obtained for the steels studied, are suitable for advanced structural applications. Originality/value: Detailed evaluation of the metallurgical purity, microstructure and fracture modes, allowed for better understanding of the microstructure-property relationships in selected high strength steels. The results obtained are of practical value for the development and production of the high strength steels with improved properties.

Słowa kluczowe

EN

metallic alloys; maraging steels; mechanical properties; microstructure

PL

stopy metaliczne; stal maraging; właściwości mechaniczne; mikrostruktura

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2008
• Tom: Vol. 27, nr 1
• Strony: 31--34
• Opis fizyczny: Bibliogr. 20 poz., il., tab., wykr.

Twórcy

autor

Pawlak S. J.

• Institute for Ferrous Metallurgy, ul. K. Miarki 12, 44-100 Gliwice, Poland,

Bibliografia

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