Capsule-free hot isostatic pressing of sintered steel to full density using water atomised iron and Cr-alloyed powder consolidated by cold isostatic pressing

Autor:	Eduard Hryha, Lars Nyborg, Ola Bergman, Sigurd Berg, Maheswaran Vattur Sundaram, Magnus Ahlfors
Rok vydání:	2021
Předmět:	Pressing Full density Materials science Metallurgy Metals and Alloys Sintering Condensed Matter Physics Iron powder Mechanics of Materials Hot isostatic pressing Powder metallurgy Materials Chemistry Ceramics and Composites Graphite Lubricant
Zdroj:	Powder Metallurgy. 65:133-140
ISSN:	1743-2901 0032-5899
Popis:	Powder metallurgy (PM) steel with enhanced density is essential for meeting the demands on high strength and high-performance applications. In this study, cold isostatic pressing (CIP) is applied for consolidating water-atomised iron and Cr-alloyed steel powder to reach about 95% densification before sintering. Additionally, the effect of the lubricant and graphite addition on the compressibility of the different base powder types was evaluated. The maximum green densities of ≈7.55 g cm−3 for iron powder and ≈7.45 g cm−3 for Cr-alloyed powder were reached after CIP at 800 MPa. The sintering at 1250°C with added graphite allowed to achieve increased densification to ≈7.60 g cm−3 for the iron and ≈7.50 g cm−3 for Cr-alloyed grades, respectively. These levels were sufficient for surface pore closure, which allowed the application of the capsule-free hot isostatic pressing (HIP) after sintering to reach full density. This approach paves the way for manufacturing large-sized PM components.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::753c86be3545b59a4293c54db89799ac https://doi.org/10.1080/00325899.2021.1966876 Zobrazit plný text záznamu