Particle deformation and microstructural evolution of high borated stainless steel consolidated by Gleeble-simulated direct powder forging

ABSTRACT

In the present work, a novel method was first proposed to realise direct powder forging of high borated stainless steel on Gleeble through hot compression tests performed at 1150°C and 0.01–10 s⁻¹ with strains of 32% and 50%. Particle deformation and microstructural evolution of high borated stainless steel powder during direct forging were investigated. Backscattered electron (BSE) and electron backscatter diffraction (EBSD) were employed for microstructure examination. Microstructure reveals that large deformation zones were easily distinguished by boride and grain features. Enhanced boride coarsening in the contact area of powders was attributed to the combined action of strain, dislocation, stress and temperature rising. Strain rates had no obvious influence on densification but significantly affected the deformation of particles. Furthermore, the mechanism of particle deformation enhanced by a higher strain rate was discussed.

KEYWORDS:

• Direct powder forging
• borated stainless steel
• microstructure
• particle deformation
• boride

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Xuan Zhou

Xuan Zhou, a researcher on stainless steel, zirconium alloys and superalloys, obtained the PhD from the School of Materials Science and Engineering, Yanshan University. This paper was mainly is completed during the PhD. I am now working for a company on zirconium alloys research. Among mine recent papers: Secondary γ′ evolution and relationship to hot deformation behavior of a supersolvus-treated superalloy with high precipitate volume fraction. Materials Science and Engineering: A 761: 138046.

Mingjia Wang

Mingjia Wang, a professor on stainless steels, special steels and superalloys. He is the doctoral supervisor of first author and work for Yanshan University. Among his recent papers: Effect of borides on hot deformation behavior and microstructure evolution of powder metallurgy high borated stainless steel. Materials Characterization 124: 182–191.