Research on the replacement of traditional milling media for the manufacturing of WC-Co tools

PhD Thesis

Scientific Supervisor

This study was conducted to determine the feasibility of an aqueous milling process in the production of WC Co powders for cemented carbides. Employing an aqueous milling process would improve the economic aspects significantly considering the raw materials’ significantly lower price, as well as the reducing the environmental impact as compared to the traditional organic solvent processing routes.
The PhD thesis was awarded the highest distinction “Summa cum laude” meaning “with outstanding praise”, typically awarded only in extraordinary circumstances.
The main objective of the thesis was to study the possibility to use the aqueous route in order to replace the conventional organic media route for the milling of raw material powders in the manufacturing process of cemented carbides tools. The comparative study took into account the mechanical – physical – chemical mechanisms that acted during the milling and subsequent drying of powders, as well as the induced effects upon the structural characteristics of resulted particles and upon the quality of the die-pressed, subsequently sintered compacts.

The results obtained in this thesis were presented at various international conferences, either poster or oral presentation:

1. H.F. Chicinaș, Aqueous hard metal processing, Doctoral Workshop – 4th International Conference on Production Research – Regional Conference Africa, Europe and the Middle East ICPR-AEM 2016, Cluj-Napoca, Romania – oral presentation – presenting author.
2. H.F. Chicinaș, Aqueous hard metal processing, Doctoral Workshop – 4th International Conference on Production Research – Regional Conference Africa, Europe and the Middle East ICPR-AEM 2016, Cluj-Napoca, Romania – poster.
3. H.F. Chicinaş, T.F. Marinca, P. Götze, A. Eckert, C.O. Popa, Influence of aqueous milling duration on the sintering ability of some hard metal powders, 10th International Conference on Materials Science & Engineering BraMat 2017, Brașov, România – oral presentation.
4. H.F. Chicinaş, A. Cotai, D.O. Jucan, T.F. Marinca, B.V. Neamțu, G. Conțiu, A. Mesaroș, P. Götze, A. Eckert, C.O. Popa, Influence of milling media on the structure and morphology of some hard metal powders,, 5th International Conference on Powder Metallurgy & Advanced Materials RoPM&AM 2017, Cluj- Napoca, România – oral presentation.

The results of this study were the subject of several articles published in ISI journals:

1. H.F. Chicinaș, T.F. Marinca, P. Götze, A. Eckert, C.O. Popa, Influence of aqueous milling duration on the sintering ability of some hard metal powders, Journal of Materials Science 53 (2018) 2901-2910 – IF 3.442.
2. H.F. Chicinaș, D.O. Jucan, T.F. Marinca, B.V. Neamțu, G. Conţiu, P. Götze, A. Eckert, C.O. Popa, Influence of milling media on the structure and agglomeration behaviour of some hard-metal powder, Powder Metallurgy (2018) – IF 1.793.
3. H.F. Chicinaș, G. Conţiu, N.A. Sechel, T.F. Marinca, A. Mesaroș, P. Götze, A. Eckert, G. Stoian, C. Leostean, O. Pana, N. Lupu, C.O. Popa, Preparation and characterisation of WC-10Co powders obtained by aqueous milling, Ceramics International 44 (18), 22935-22942 – IF 3.830.
Contact:
horea.chicinas@stm.utcluj.ro
Department of Materials Science and Engineering
Technical University of Cluj-Napoca
103-105 Muncii Avenue 400641 Cluj-Napoca
Tel: +40 728 868 016