In-Situ Surface Integrity Study Focused On Cobalt Phase Transformation Induced During The Grinding And Polishing Process In Cemented Carbides WC-Co Surfaces

Authors:

G. Riu-Perdrix (1,2), A. Isalgué (3), N. Cinca (4), L. Llanes (2), J.J. Roa (1)

1- Steros GPA Innovative S.L., Barcelona, Spain

2- CIEFMA-Department of Materials Science and Engineering – Universitat Politècnica de Catalunya – BarcelonaTech, Campus Diagonal Besos-EEBE, Barcelona, Spain

3- Dep. Física, Universitat Politècnica Catalunya, Barcelona, Spain

4- Hyperion Materials & Technologies, Pol. Ind., Martorelles, Spain

Abstract:

The surface integrity in terms of phase transformation for the metallic cobalt (Co) binder and compressive residual stresses (scomp) on ground WC-10wt.%Co specimens and sequentially dry-electropolished was studied by means of synchrotron radiation. In-situ heating up to 900ºC helped in monitoring the reverse transformation induced during the pre-processing process, from h.c.p- to f.c.c-Co. It was revealed that as the dry-electropolishing process time increased, the full width at half maximum of XRD peaks decreases, associated with slight reduction of the distribution of the scomp near the surface of the specimens. In addition, both ground and dry-electropolished specimens exhibited a release in scomp as result of the thermal treatment. Deeper study on the Co phase revealed that on heating, the h.c.p. peak intensity decreased, specially for the polished samples, while the f.c.c. one increased, confirming the h.c.p to f.c.c phase reversion reaction for the metallic Co binder.

DOI:

https://doi.org/10.59499/EP246286628