Growth inhibiting during ultra-high temperature sintering of injection moulded 17-4 PH stainless steel through the dispersion of ZrO₂ particle as a thermal stabiliser

ABSTRACT

The present work deals with the metal injection moulding and ultra-high temperature sintering of 17-4 PH powder. Purposefully, 5 mass% ZrO₂ particles were dispersed by applying high shear stress during feedstock preparation. Uniformly distributed particles effectively hindered the powder boundary migration and limited their growth during ultra-high sintering temperatures. The achieved thermal stability provided a proper condition for reducing the final porosity to 3% and significantly improved the ultimate strength to 1070 MPa after sintering at 1380°C. Also, the ZrO₂ particles acted as facilitators of sliding between solid powders and substantially reduced the required pressure for injecting to 700 Bar. Through introducing such a new approach in the field of powder injection moulding by ZrO₂ particles, the amount of anisotropic shrinkage was reduced to 2%.

KEYWORDS:

• Pining effect
• thermal stability
• shrinkage
• mechanical properties

Disclosure statement

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

Additional information

Notes on contributors

Masoud Moradjoy

Masoud Moradjoy is a Ph.D. Candidate at the faculty of materials science and engineering, K. N. Toosi University of Technology, Tehran, Iran, with a focus on the powder metallurgy of stainless steel alloys, especially in the field of biomaterial and dental implant injection molding.

Hamid Khorsand

Hamid Khorsand is an Associate Professor at the faculty of materials science and engineering, K. N. Toosi University of Technology, Tehran, Iran, with a focus on all processes of powder metallurgy of stainless steel alloys, especially in the field of the new application of powder science in the automobile industry.