Load-Adapted Surface Modifications to Increase Lifetime of Forging Dies

Abstract:

Diffusion treatments offer possibilities to enhance the performance and the service lifetime of hot forging tools. In combination with coating after nitriding, the surface layer hardness can be further increased. Within the scope of this study, a surface layer hardness above 2,000 HV0.005 was determined for borided or DLC (diamond-like carbon) coated surface layers. An increased surface layer hardness improves the abrasive wear resistance of forging dies. Furthermore, the plastic deformation of thermally softened forging die areas can be reduced. Beside these desirable effects, the ductility of diffusion treated or coated near surface layers is reduced and thermomechanical cracks are promoted. Therefore, additional approaches were developed to improve the thermomechanical crack behaviour of forging dies. Patterned plasmanitriding by the use of coverages to prevent areas from nitrogen diffusion, new combination processes of plasmanitrocarburizing (PNC) followed by plasmanitriding (PN) and the innovative boriding were investigated on different abstraction levels. A system of several testing rigs was set up to enable the abstraction of the thermal shock conditions in different stages. The patterned nitriding, boriding and combination plasma process (PN + PNC) were evaluated in a series of industrial field tests to derive recommendations for suitable tool treatments.

• Periodical: Key Engineering Materials (Volume 926)
• Pages: 1178-1187
• DOI: https://doi.org/10.4028/p-5l24m7
• Online since: July 2022
• Authors: Hanno Paschke*, Martin Weber, Kai Brunotte, Marcel Rothgänger, Tom Petersen, Martin Siegmund, Julius Peddinghaus
• Keywords: Boriding, Diamond-Like Carbon, Diffusion Treatment, Forging, Load Adapted Modification, Thermal Shock Condition, Wear

References

[1] Z. Gronostajskj, M. Kaszuba, H. Paschke, T. Zakrzewski, G. Rogaliński, Improvement Of Tools Durability by Application of Hybrid Layer of Nitrided/PECVD Coating, Archives of Metallurgy and Materials 60 (2015) 1609 – 1615.

DOI: 10.1515/amm-2015-0281

[2] S. Joshy, K.R. Jayadevan, A. Ramesh, D. Mahipal, Influence of in-service thermal softening on wear and plastic deformation in remanufactured hot forging dies, Engineering Research Express 1 (2019) 025024.

DOI: 10.1088/2631-8695/ab504f

[3] R. Ebara, Fatigue crack initiation and propagation behavior of forging die steels, International Journal of Fatigue 32 (2010) 830 – 840.

DOI: 10.1016/j.ijfatigue.2009.07.020

[4] A. Klassen, A. Bouguecha, B.-A. Behrens, R. Bernhardt, Charakterisierung der Härteveränderung von Schmiedewerkzeugen unter zyklischer thermischer Beanspruchung, Schmiede-Journal 9 (2014) 34–37.

[5] A. Fissolo, S. Amiable, S., O. Ancelet, Crack initiation under thermal fatigue. An overview of CEA experience. Thermal fatigue appears to be more damaging than uniaxial isothermal fatigue. International Journal of Fatigue 31 (2009) 587 – 600.

DOI: 10.1016/j.ijfatigue.2008.03.038

[6] H. Paschke, M. Mejauschek, M. Weber, K. Brunotte, M. Siegmund, J. Peddinghaus, D. Lenz, G. Braeuer, B.-A. Behrens, P. Dueltgen, Life time enhancement of forging dies with tailored diffusion treatments, International Tooling Conference 2019, Aachen.

DOI: 10.1063/1.5034870

[7] Paschke, H.; Lippold, L.; Brunotte, K.: Adapted surface properties of hot forging tools using plasma technology for an effective wear reduction, Wear 330 – 331 (2015) 429 – 438.

DOI: 10.1016/j.wear.2015.02.009

[8] T. Yilkiran, B.-A. Behrens, H. Paschke, M. Weber, H. Brand, The potential of plasma deposition techniques in the application field of forging processes, Archives of Civil and Mechanical Engineering 12 (2012) 284 – 291.

DOI: 10.1016/j.acme.2012.06.002

[9] M. Weber, M. Mejauschek, H. Paschke, R. Leisner, G. Braeuer, P. Kaestner, J. Vogtmann, T. Petersen, J. Wessel, Plasmaboriding of high-alloyed tool steels – A new approach for wear reduction on highly loaded forming tools, 16th Int. Conference on Plasma Surface Engineering, Garmisch-Partenkirchen, (2018).

[10] S. Jegou, L. Barrallier, R. Kubler, Phase transformations and induced volume changes in a nitrided ternary Fe-3%Cr-0.345C alloy, Acta Materialia 58 (2010) 2666 – 2676.

DOI: 10.1016/j.actamat.2009.12.053