Development of a new model describing the anisotropic dimensional change on sintering

ABSTRACT

The anisotropic dimensional changes during sintering were investigated for rings made of eight different materials with different green densities and H/(D_ext−D_int) ratio. Dimensional changes are affected by green density, as shown in previous works, while the geometrical parameter does not display a clear influence. The anisotropy parameter K defined in a previous work does not describe anisotropy of dimensional change unambiguously, due to the anisotropy of shrinkage/swelling in the compaction plane. A new anisotropy parameter (K_3D) was therefore defined considering the dimensional changes of internal diameter, external diameter and height. This parameter displays an unambiguous dependence on the equivalent isotropic dimensional change and will be used in further work to develop a predictive model for the prediction of the anisotropic dimensional change during sintering of parts with different green densities and geometry.

KEYWORDS:

• Dimensional change
• anisotropy

Disclosure statement

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

Additional information

Notes on contributors

Ilaria Cristofolini

Ilaria Cristofolini received the PhD degree in Metallurgical Engineering in 1995 from Padua University, Italy. She is currently associate professor of the Department of Industrial Engineering, Trento University, in the field Design methods for industrial engineering. Her main research activity is devoted to the study of design methods for powder metallurgy, to design methods against wear, to PM parts geometric dimensioning and tolerancing.

Alberto Molinari

Alberto Molinari received the PhD degree in Metallurgical Engineering from Torino technical University, Italy. He is currently a professor of the Department of Industrial Engineering, Trento University. He received Honor PhD by University Carlos III, Madrid in 2016 and by Cracow Technical University in 2019, and is Fellow of EPMA and of APMI.

Marco Zago

Marco Zago received the PhD in Materials, Mechatronics and Systems Engineering in 2020 from University of Trento and he is currently working as research fellow at the Department of Industrial Engineering, University of Trento. His major research interests include the development of design method applied to additive manufacturing and the study of anisotropic dimensional change on sintering of powder metallurgy products.

Onur Utku Uçak

Onur Utku Uçak is a PhD student in Material, Mechatronics and Systems Engineering at the University of Trento. He received the MSc in Aeronautical Engineering in 2018 from Politecnico di Milano and BSc in Aerospace Engineering in 2015 from Middle East Technical University. The PhD project is focused on Design methodologies in Powder Metallurgy.

Bruno Vicenzi

Bruno Vicenzi is Technical Manager in the European Powder Metallurgy Association (EPMA) since 2019. After graduating in Physics in 1988, in his career he has previously been a researcher on powder technologies in Centro Sviluppo Materiali Spa (now part of RINA Spa), and has later started and run a Metal Injection Moulding company in Italy, always with a focus in research, development and innovation. Within EPMA, he coordinates activities, including collaborative research projects, in the Press and Sinter, MIM and Functional Materials sectors, on the Sustainability topic, and on trainings for PM engineers and students.

Mark James Dougan

Mark James Dougan is Chief Metallurgist in the AMES PM Tech Centre, working on material and process development, failure analysis, and soft magnetic materials. He received his BSc and PhD in Metallurgy from the University of Manchester in 1991 and 1995 respectively.

Markus Schneider

Markus Schneider received his diploma degree in mechanical engineering and the master degree in safety engineering at the University of Wuppertal. The PhD study at the University of Wuppertal was about low cycle fatigue and damage of sintered components. Markus Schneider is working for GKN Sinter Metals in Radevormwald/Germany. He is the head of the global simulation activities and an expert in fatigue design, heat treatment and PM processing.

Preben Hedegard Pedersen

Preben Hedegaard Pedersen started in 1983 at Grundfos A/S. as Machine Engineer and joined in 1991 the RD department at Grundfos, a part of the RD department was working with Stainless Steel Powder Metal. In 1997 one of the 6 employees from Grundfos RD, who started up Sintex A/S. He worked from the beginning as Production Manager, today he is working as Senior Process Specialist in the PTD department at Sintex. The development of PM materials corrosion resistance and optimizing PM process are his key area.

Johanna Bolitschek

Johanna Bolitschek (born 1991) is currently working as a R&D Engineer at MIBA Sinter Austria. Prio to joining MIBA, she worked as a research associate at the Institute of Nonferrous Metallurgy, University of Leoben. She holds a Master of Science and a PhD in Metallurgy from the University of Leoben.

Juergen Voglhuber

Juergen Voglhuber is a development engineer in the R&D Material Team at Miba Sinter Austria GmbH with more than 15 years of professional experience in the field of powder metallurgy. His primary research interests focus on the subject area of powder compositions and the compacting process for existing and new applications. He graduated in 2005 from the University of Applied Sciences in Wels with a DI (FH) in Automation Technology.