Effect of Density and Processing Conditions on Oxide Transformations and Mechanical Properties in Cr–Mo-Alloyed PM steels
Artikel i vetenskaplig tidskrift, 2022

To improve the mechanical properties and performances of water-atomized powder metallurgy steels, it is necessary to enhance the density. Consolidating water-atomized steel powders via conventional pressing and sintering to a relative density level > 95 pct involves processing challenges. Consolidation of gas-atomized powders to full density by hot isostatic pressing (HIP) is an established process route but utilizing water-atomized powders in HIP involves challenges that result in the formation of prior particle boundaries due to higher oxygen content. In this study, the effect of density and processing conditions on the oxide transformations and mechanical properties from conventional press and sintering, and HIP are evaluated. Hence, water-atomized Cr–Mo-alloyed powder is used and consolidated into different density levels between 6.8 and 7.3 g cm−3 by conventional die pressing and sintering. Fully dense material produced through HIP is evaluated not only of mechanical properties but also for microstructural and fractographic analysis. An empirical model based on power law is fitted to the sintered material properties to estimate and predict the properties up to full density at different sintering conditions. A model describing the mechanism of oxide transformation during sintering and HIP is proposed. The challenges when it comes to the HIP of water-atomized powder are addressed and the requirements for successful HIP processing are discussed.

Författare

Maheswaran Vattur Sundaram

Höganäs

Eduard Hryha

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Dimitris Chasoglou

Höganäs

Anna Rottstegge

Reifenhäuser Reiloy GmbH

Lars Nyborg

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

1073-5623 (ISSN)

Vol. 53 2 640-652

Ämneskategorier

Keramteknik

Materialkemi

Metallurgi och metalliska material

DOI

10.1007/s11661-021-06539-4

Mer information

Senast uppdaterat

2022-04-05