Processing of 17Cr7Mn6Ni TRIP Steel Powder by Extrusion at Room Temperature and Pressureless Sintering. Issue 6 (20th April 2020)

• Record Type: Journal Article
• Authors: Baumgart, Christine; Weigelt, Christian; Lißner, Andreas; Martin, Stefan; Aneziris, Christos G.; Krüger, Lutz
• Is Part Of: Advanced engineering materials. Volume 22:Issue 6(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-04-20
• Subjects: hydrogen sintering -- powder metallurgy -- reduction process -- TRIP steel -- XPS analysis; Materials -- Periodicals; 620.11
• DOI: 10.1002/adem.202000019
• Languages: English
• ISSNs: 1438-1656

Abstract

Abstract : Transformation‐induced plasticity (TRIP) steels are known for their outstanding strength and their excellent deformation properties, which are necessary for the improvement of occupant safety elements in air, rail and motor vehicles. One precondition for the realization of the TRIP effect is the creation of a metastable austenitic microstructure through the addition of a number of alloying elements. The great affinity of some alloying elements for oxygen implies the formation of highly stable oxides during thermal processing. In the current study, an extrusion process (derived from the processing of ceramics) with subsequent debinding and pressureless sintering is used to manufacture compact strands from prealloyed and gas‐atomized 17Cr7Mn6Ni TRIP steel powder. The influence of both the debinding temperature and sintering atmosphere on the oxide particle content in the final bulk product are investigated by X‐ray diffraction (XRD) analysis and quantitative metallography. Furthermore, X‐ray photoelectron spectroscopy (XPS) analysis in association with temperature‐programmed reduction (TPR) experiments, thermogravimetric (TG) measurements and mass/infrared spectroscopy (MS/IRS) serve to monitor the changes in the steel powder surface composition and the effectiveness of hydrogen as a reducing agent. Abstract : Varying debinding temperatures and sintering atmospheres are applied to extruded strands consisting of 17Cr7Mn6Ni TRIP steel powder to investigate the influence on the oxide particle content in the final bulk product. The effectiveness of both approaches are assessed by XRD and quantitative metallography. Various methods are used to describe the processes during hydrogen sintering resulting in the lowest particle content.