A Review of Methods for Increasing the Durability of Hot Forging Tools
Abstract
1. Introduction
2. Methods for Improving the Durability of Forging Dies
- 1.
- Methods related to the entire tool (selection of tool material and appropriate heat treatment and optimization of tooling shape and design);
- 2.
- Methods related to the surface layer (hybrid techniques, thermochemical treatment, and welding and mechanical methods);
- 3.
- Other methods not directly related to the tool (supervision systems allowing for full monitoring of the process and solutions allowing for effective extension of the service life of forging tools).
- 1.
- Design measures include but are not limited to the following:
- –
- Selection of the chemical composition of the tool material, enabling the production process to obtain the appropriate microstructure and properties throughout the volume and within the surface layer of the manufactured tool;
- –
- Proper design of forgings;
- –
- Proper selection of the number and type of die cuts and the correct design of their stereometric shape and dimensions as well as surface roughness characteristics.
- 2.
- Technological means, which include the use of advanced methods of shaping, finishing, and surface treatment, such as plastic working, abrasive and electrochemical treatment (electro-polishing), burnishing (to impart high smoothness and introduce ultimate compressive stresses into the surface layer), heat and thermochemical treatment, and electro-spark strengthening.
- 3.
- Operating measures, which include, among others, the use of running-in and appropriate lubrication and cooling media, as well as ensuring the proper technical condition of forging machines and devices, compliance with the dates of periodic inspections, and other recommendations of the manufacturers of equipment and materials used in the production process.
- –
- To use high-alloy, wear-resistant, and thermo-mechanical fatigue-resistant tool steels;
- –
- To design multi-element forging dies assembled with working elements made of materials with high mechanical properties;
- –
- To use strengthening surface treatment, e.g., burnishing.
2.1. Durability of Forging Tools in Relation to the Chemical Composition of Hot-Work Tool Steels
2.2. The Influence of Design and Technology on the Production of Dies and Forging Equipment and Errors in the Technological Process
2.3. Influence of the Heat Treatment Process and Defects Occurring
- 1.
- Decarburization and oxidation of the surface during prolonged heating at high temperature.
- 2.
- Excessive austenite grain growth and the associated reduction of plastic properties and impact strength caused by too high a temperature (overheating) and long heating time during austenitizing.
- 3.
- Loss of the secondary hardness effect after tempering and reduced tempering resistance. These defects arise due to low saturation of austenite with alloying elements and carbon during hardening from too low a temperature (underheating).
- 4.
- Low-strength properties caused by the formation of microstructures consisting of carbides and ferrite not saturated enough with alloying elements. This defect is caused by too slow cooling from the austenitizing temperature.
2.4. Engineering Methods for Improving the Surface Layers of Forging Dies
- –
- Techniques involving thermochemical treatment (diffusion layers);
- –
- CVD and PVD techniques;
- –
- Mechanical techniques (e.g., burnishing, shot peening, and discing);
- –
- Beam techniques (e.g., ion implantation and laser processing);
- –
- Hybrid techniques.
2.5. Forging Process Technology and Exploitation Conditions
- –
- Shape of the forging (axially symmetrical, compact, elongated, and complex) and mass of the forging;
- –
- Kinematics of material flow on various forging machines (hammers, presses, forging machines, and aggregate sets);
- –
- Plastic and mechanical properties of the deformed material, taking into account the forging temperature (cold or hot);
- –
- Matrix construction (open and closed).
3. Principles of Manufacturing Dies from 42CrMo4 Steel by Surfacing Working Surfaces and Properties of Surfaced Layers on Forging Die Blanks
Comparative Durability of Forging Dies Made of 37CrMoV5-1 (WCL) and 42CrMo4 Steel with Hard-Facing Surfaces of Cut-Outs
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
Abbreviation | Description |
X37CrMoV5-1 | Hot-work tool steel according to EN ISO 4957 |
1.2343 | DIN designation equivalent to X37CrMoV5-1 |
H11 | AISI designation equivalent to X37CrMoV5-1 |
42CrMo4 | Alloy structural steel used as a die material substitute |
1.7225 | DIN designation for 42CrMo4 |
55H3SMF | Polish Cr-Mo-V steel with sulfur for improved machinability |
4340 mod. | AISI equivalent to 55H3SMF (with V, S) |
41HMFS | Polish equivalent to 42CrMo4 with added V and S |
4140 mod. | AISI equivalent to 41HMFS (with V, S) |
50H2SF | Polish Cr-V spring or structural steel with sulfur |
50CrV4 | EN designation for spring steel similar to 50H2SF |
1.8159 | DIN designation for Cr-V spring steel |
6150 | AISI equivalent to 50H2SF |
F-818 | Fully martensitic wire, ideal for high-wear and abrasive conditions |
F-812 | Martensitic-bainitic wire with surface ferrite, suitable for thermo-mechanical fatigue |
UTOP38 | Dual-phase wire with rich ferritic content, effective under extreme fatigue |
References
- Satyam, K.; Srivastava, D.P.; Kumar, S.; Ohdar, R. Parametric optimization of hot forging process: A six sigma based approach. In Proceedings of the E3S Web of Conferences, Hyderabad, India, 24–26 December 2021; EDP Sciences: Les Ulis, France, 2021; Volume 309, p. 01159. [Google Scholar]
- Antony, J.; Kumar, M.; Tiwari, M.K. An application of Six Sigma methodology to reduce the engine-overheating problem in an automotive company. Proc. Inst. Mech. Eng. Part B J. Eng. Manuf. 2005, 219, 633–642. [Google Scholar] [CrossRef]
- Brucelle, O.; Bernhart, G. Methodology for service life increase of hot forging tools. J. Mater. Process. Technol. 1999, 87, 237–246. [Google Scholar] [CrossRef]
- Behrens, B.A.; Schäfer, F.; Bistron, M. Investigations on forging dies with ceramic inserts by means of finite-element-analysis. In Proceedings of the AIP Conference Proceedings, Porto, Portugal, 17–21 June 2007. [Google Scholar]
- Buchmayr, B. Damage, Lifetime, and Repair of Forging Dies. BHM Berg- und Hüttenmännische Monatshefte 2017, 162, 88–93. [Google Scholar] [CrossRef]
- Briefs, H.; Wolf, M. Warmarbeitsstähle; Verlag Stahleisen GmbH: Düsseldorf, Germany, 1975. [Google Scholar]
- Čamek, L.; Jelen, L. Increasing material durability for drop hot forging. In Proceedings of the METAL 2009-18th International Conference on Metallurgy and Materials, Conference Proceedings, Hradec nad Moravicí, Czech Republic, 19–21 May 2009. [Google Scholar]
- Daouben, E.; Dubois, A.; Dubar, M.; Dubar, L.; Deltombe, R.; Truong Dinh, N.G.; Lazzarotto, L. Effects of lubricant and lubrication parameters on friction during hot steel forging. Int. J. Mater. Form. 2008, 1, 1223–1226. [Google Scholar] [CrossRef]
- Di Lorenzo, R.; Corona, V.; Micari, F. Hot impression die forging process: An approach to flash design for tool life improvement. In Proceedings of the AMST’05 Advanced Manufacturing Systems and Technology: Seventh International Conference, Udine Italy, 1 July 2005; Springer: Berlin/Heidelberg, Germany, 2025; pp. 465–472. [Google Scholar]
- Duchek, M.; Koukolikova, M.; Kotous, J.; Majer, M. Increasing of the lifetime of large forging dies by repairwelding. IOP Conf. Ser. Mater. Sci. Eng. 2018, 307, 012011. [Google Scholar] [CrossRef]
- Farhani, M.; Amadeh, A.; Kashani, H.; Saeed-Akbari, A. The study of wear resistance of a hot forging die, hardfaced by a cobalt-base superalloy. Mater. Forum 2006, 30, 212–218. [Google Scholar]
- Gronostajski, Z.; Hawryluk, M.; Kaszuba, M.; Marciniak, M.; Niechajowicz, A.; Polak, S.; Zwierzchwoski, M.; Adrian, A.; Mrzygłód, B.; Durak, J. The expert system supporting the assessment of the durability of forging tools. Int. J. Adv. Manuf. Technol. 2015, 82, 1973–1991. [Google Scholar] [CrossRef]
- Gronostajski, Z.; Kaszuba, M.; Polak, S.; Zwierzchowski, M.; Niechajowicz, A.; Hawryluk, M. The failure mechanisms of hot forging dies. Mater. Sci. Eng. A 2016, 657, 147–160. [Google Scholar] [CrossRef]
- Gronostajski, Z.; Hawryluk, M.; Jakubik, J.; Kaszuba, M.; Misiun, G.; Sadowski, P. Solution examples of selected issues related to die forging. Arch. Metall. Mater. 2015, 60, 2767–2775. [Google Scholar] [CrossRef]
- Gronostajski, Z.; Widomski, P.; Kaszuba, M. Analiza trwałości wkładek matrycowych do kucia na gorąco widłaka wykonanych ze stali 1.2343 i UNIMAX. Rudy Met. Nieżelazne Recykling 2018, 63, 9–18. [Google Scholar] [CrossRef]
- Hawryluk, M.; Gronostajski, Z.; Ziemba, J.; Dworzak, Ł.; Jabłoński, P.; Rychlik, M. Analysis of the influence of lubrication conditions on tool wear used in hot die forging processes. Eksploat. Niezawodn.–Maint. Reliab. 2018, 20, 169–176. [Google Scholar] [CrossRef]
- Guo, Y.; Liu, W.; Sun, M.; Xu, B.; Li, D. A method based on semi-solid forming for eliminating coarse dendrites and shrinkage porosity of H13 tool steel. Metals 2018, 8, 277. [Google Scholar] [CrossRef]
- Pytel, S.; Turek, J.; Okoński, S.; Zarębski, K. The properties and microstructure of padding welds built up on the surface of forging dies. Arch. Foundry Eng. 2010, 10, 205–215. [Google Scholar]
- Pytel, S.; Turek, J.; Okoński, S.; Zarębski, Z. Struktura i własności warstw napawanych na powierzchniach wykrojów matryc kuźniczych. In Proceedings of the Materiały Jubileuszowej Międzynarodowej Konferencji Naukowej: Jakość i Innowacyjność w Procesach Wytwarzania, Politechnika Krakowska, Zakopane, Poland, 23–25 September 2010. [Google Scholar]
- Krajewska-Spiewak, J.; Turek, J.; Gawlik, J. Maintenance Supervision of the Dies Condition and Technological Quality of Forged Products in Industrial Conditions. Manag. Prod. Eng. Rev. 2021, 12, 1–12. [Google Scholar] [CrossRef]
- Turek, J.; Okoński, S.; Piekoszewski, W. Badanie odporności na ścieranie warstw napawanych i stali narzędziowych na matryce kuźnicze. Obróbka Plastyczna Metali 2012, 23, 39–44. [Google Scholar]
- Turek, J.; Pytel, S.; Okoński, S. Badanie mikrostrukturalne i fraktograficzne warstw napawanych na wykrojach matryc kuźniczych. Obróbka Plastyczna Metali 2016, 27, 33–43. [Google Scholar]
- Turek, J.R. Struktura i włAściwości Warstw Napawanych na Wykrojach Matryc kuźNiczych; Politechnika Krakowska: Kraków, Poland, 2019. [Google Scholar]
- Turek, J. Wybrane problemy eksploatacji matryc kuźniczych w warunkach produkcyjnych. In Inżynieria Zarządzania. Aktualności Badawcze 2; PWE: Warszawa, Poland, 2020. [Google Scholar]
- Widomski, P.; Gronostajski, Z. Comprehensive Review of Methods for Increasing the Durability of Hot Forging Tools. Procedia Manuf. 2020, 47, 349–355. [Google Scholar] [CrossRef]
- Krawczyk, J.; Łukaszek Sołek, A.; Śleboda, T.; Lisiecki, Ł.; Bembenek, M.; Cieślik, J.; Góral, T.; Pawlik, J. Tool wear issues in hot forging of steel. Materials 2023, 16, 471. [Google Scholar] [CrossRef]
- Ficak, G.; Łukaszek Sołek, A.; Hawryluk, M. Durability of Forging Tools Used in the Hot Closed Die Forging Process—A Review. Materials 2024, 17, 5407. [Google Scholar] [CrossRef]
- Andronov, V.; Pitrmuc, Z.; Zajíc, J.; Šotka, P.; Beránek, L.; Bock, M. Conformal cooling as a support tool for eliminating local defects in high-pressure die casting series production. Prog. Addit. Manuf. 2025, 10, 1511–1528. [Google Scholar] [CrossRef]
- Hawryluk, M.; Janik, M.; Gronostajski, Z.; Barełkowki, A.; Zwierzchowski, M.; Lachowicz, M.; Ziemba, J.; Marzec, J. Possibilities of Increasing the Durability of Punches Used in the Forging Process in Closed Dies of Valve Forgings by Using Alternative Materials from Tool Steels and Sintered Carbides. Materials 2024, 17, 370. [Google Scholar] [CrossRef] [PubMed]
- Hawryluk, M.; Janik, M.; Zwierzchowski, M.; Lachowicz, M.M.; Krawczyk, J. Possibilities of increasing the durability of dies used in the extrusion process of valve forgings from chrome-nickel steel by using alternative materials from hot-work tool steels. Materials 2024, 17, 346. [Google Scholar] [CrossRef]
- Kapuściński, J.; Macyszyn, Ł.; Zieliński, M.; Meller, A.; Lehmann, M.; Bartkowiak, T. Effect of Surface Finishing and Nitriding on the Wetting Properties of Hot Forging Tools. Materials 2025, 18, 172. [Google Scholar] [CrossRef]
- Wang, S.; Wang, F.; Cui, X. A newly-developed high wear resistant cast hot-forging die steel. ISIJ Int. 2007, 47, 1335–1340. [Google Scholar] [CrossRef]
- Hawryluk, M. Review of selected methods of increasing the life of forging tools in hot die forging processes. Arch. Civ. Mech. Eng. 2016, 16, 845–866. [Google Scholar] [CrossRef]
- Hawryluk, M.; Widomski, P.; Ziemba, J. Analiza przyczyn występowania nagłych uszkodzeń narzędzi kuźniczych. Obróbka Plastyczna Metali 2017, 28, 75–92. [Google Scholar]
- Hawryluk, M.; Widomski, P.; Kaszuba, M.; Polak, S. Methods of temperature determination and measurement verification in applications related to hot die forging processes. High Temp.-High Press. 2020, 49, 1–15. [Google Scholar] [CrossRef]
- Noelke, C.; Luecke, M.; Kaierle, S.; Wesling, V.; Overmeyer, L. Laser-dispersing of forging tools using AlN-ceramics. In In Proceedings of the High-Power Laser Materials Processing: Lasers, Beam Delivery, Diagnostics, and Applications III, San Francisco, CA, USA, 4–6 February 2014. [Google Scholar]
- Koning, H.D.; Mast, J. A Rational Reconstruction of Six Sigma’s Breakthrough Cookbook, Optimizing Six Sigma Strategies to Improve Your Bottom Line. In Proceedings of the First International Conference on Six Sigma, Glasgow, UK, 16–17 December 2004. [Google Scholar]
- Turek, J.R. Structure and Properties of Layers Deposited on Forging Die Impressions; Monographic Publishing Series; Cracow University of Technology: Cracow, Poland, 2019; ISBN 978-83-65991-82-9. [Google Scholar]
- Thomas, A. DFRA Forging Handbook–Die Design; Drop Forging Research Association: Sheffield, UK, 1995. [Google Scholar]
- Łataś, Z.; Ciski, A.; Suchmann, P. Cryogenic treatment of hot forging dies. In Proceedings of the Proceedings-15th IFHTSE-International Federation for Heat Treatment and Surface Engineering Congress 2006, Vienna, Austria, 26 September 2006. [Google Scholar]
- Deshpande, M.N.; Altan, T. Selection of Die Materials and Surface Treatments for Increasing Die Life in Hot and Warm Forging; Technical Report No. 644–fia, ERC for Net Shape Forming; The Ohio State University: Columbus, OH, USA, 2011. [Google Scholar]
- Xu, W.; Li, W.; Wang, Y. Experimental and theoretical analysis of wear mechanism in hot-forging die and optimal design of die geometry. Wear 2014, 318, 78–88. [Google Scholar] [CrossRef]
- Kang, J.; Park, I.; Jae, J.; Kang, S. A study on die wear model considering thermal softening (II): Application of the suggested wear model. J. Mater. Process. Technol. 1999, 94, 183–188. [Google Scholar] [CrossRef]
- Raghavendra Rao, T.R.; Biswas, S.K. Experimental investigation of die wear in small-batch hammer-forging under unlubricated conditions. J. Mech. Work. Technol. 1979, 3, 137–150. [Google Scholar] [CrossRef]
- Lange, K.; Cser, L.; Geiger, M.; Kals, J. Tool life and tool quality in bulk metal forming. CIRP Ann. 1992, 41, 667–675. [Google Scholar] [CrossRef]
- Sharma, R.; Arrowsmith, D. The wear of forging dies in the first five forging blows. Wear 1981, 74, 1–10. [Google Scholar] [CrossRef]
- Gierzyńska-Dolna, M.; Lacki, P.; Plewiński, A.; Szyndler, R. Nowoczesne sposoby podnoszenia trwałości narzędzi do pracy na gorąco wysokoefektywnymi metodami inżynierii powierzchni. Rudy Met. Nieżelazne 2001, 46, 583–586. [Google Scholar]
- Marashi, J.; Yakushina, E.; Xirouchakis, P.; Zante, R.; Foster, J. An evaluation of H13 tool steel deformation in hot forging conditions. J. Mater. Process. Technol. 2017, 246, 276–284. [Google Scholar] [CrossRef]
- Kwon, H.H.; Bramely, A.N. Development of ceramic inserts for forging tools. CIRP Ann.-Manuf. Technol. 2000, 49, 173–176. [Google Scholar] [CrossRef]
- Yilkiran, T.; Behrens, B.A.; Buchmayr, B. Maßnahmen zur Reparatur und Lebensdauererhöhung von Schmiedewerkzeugen. Schmiede-J. 2012, 3, 52–57. [Google Scholar]
- Buchmayr, B. Reparaturtechnologien-Übersicht der Möglichkeiten. In Proceedings of the Workshop Schmiedewerkzeuge, Conference Schmiedewerkzeuge, Salzburg, Austria, 24–25 October 2011. [Google Scholar]
- Cui, X.H.; Shan, J.; Yang, Z.R.; Wei, M.X.; Wang, S.Q.; Dong, C. Alloying Design for High Wear-Resistant Cast Hot-Forging Die Steels. J. Iron Steel Res. Int. 2008, 15, 67–72. [Google Scholar] [CrossRef]
- JIS G 4404:1983; Alloy Tool Steels. Japanese Standards Association/Japanese Industrial Standards Committee: Tokyo, Japan, 1983; Technical Report, Standard Published by JSA/JISC.
- Oudin, J. Life prediction of hot work tool steels subjected to thermo-mechanical fatigue. Matériaux Tech. 2000, 88, 67–72. [Google Scholar] [CrossRef]
- Jia, Z.; Ji, J. Influence analysis of shot peening on hot forging die. Int. J. Adv. Manuf. Technol. 2017, 90, 1779–1787. [Google Scholar] [CrossRef]
- Liu, Y.; Wu, Y.; Wang, J.; Liu, S. Defect analysis and design optimization on the hot forging of automotive balance shaft based on 3D and 2D simulations. Int. J. Adv. Manuf. Technol. 2018, 94, 2739–2749. [Google Scholar] [CrossRef]
- Klimpel, A. Napawanie i Natryskiwanie Cieplne; WNT: Warszawa, Poland, 2000. [Google Scholar]
- Mazur, A.; Pacyna, J. Ocena ciągliwości stali narzędziowych do pracy na gorąco za pomocą współczynnika intensywności naprężeń KIc-Assessment of the Ductility of Hot-Work Tool Steels Using the Stress-Intensity Factor, KIc. Hutnik (Katowice) 1977, 44, 468–473. [Google Scholar]
- Klobčar, D.; Tušek, J.; Taljat, B. Thermal fatigue of materials for die-casting tooling. Mater. Sci. Eng. A 2008, 472, 198–207. [Google Scholar] [CrossRef]
- Buchmayr, B. (Ed.) Workshop Schmiedewerkzeuge; Montanuniversität Leoben, Lehrstuhl für Umformtechnik: Leoben, Austria, 2011; ISBN 978-3-902078-16-2. [Google Scholar]
- Płaza, S.; Margielewski, L.; Celichowski, G. Wstęp do Tribologii i Tribochemii-Introduction to Tribology and Tribochemistry; Monograph Introducing Tribology and Tribochemistry; Wydawnictwo Uniwersytetu Łódzkiego: Łódź, Poland, 2005; p. 420. [Google Scholar]
- Shinde, T.; Dhokey, N. Evolution of tertiary carbides and its influence on wear behavior, surface roughness and fatigue limit of die steels. In Proceedings of Fatigue, Durability and Fracture Mechanics; Springer: Singapore, 2017; pp. 237–252. [Google Scholar]
- Ebara, R. Fatigue and fracture behavior of forging die steels. In New Trends and Developments in Automotive System Engineering; IntechOpen: London, UK, 2011; pp. 47–64. [Google Scholar]
- Mang, T.; Bobzin, K.; Bartels, T. Industrial Tribology: Tribosystems, Friction, Wear and Surface Engineering, Lubrication; John Wiley & Sons: Hoboken, NJ, USA, 2011. [Google Scholar]
- Foster, J.; Cullen, C.; Fitzpatrick, S.; Payne, G.; Hall, L.; Marashi, J. Remanufacture of hot forging tools and dies using laser metal deposition with powder and a hard-facing alloy Stellite 21®. J. Remanuf. 2019, 9, 189–203. [Google Scholar] [CrossRef]
- Boljanovic, V. Metal Shaping Processes: Casting and Molding, Particulate Processing, Deformation Processes, and Metal Removal; Industrial Press Inc.: South Norwalk, CT, USA, 2010. [Google Scholar]
- Mazurkiewicz, A.; Smolik, J. Innowacyjne kierunki rozwoju i wdrożeń technologii hybrydowych w inżynierii powierzchni-Innovative directions of development and implementation of hybrid technologies in surface engineering. Archiwum Metalurgii i Materiałów 2015, 60, 2161–2172. [Google Scholar] [CrossRef]
- Nielsen, C.; Bay, N. Review of frictiociesn modeling in metal forming processes. J. Mater. Process. Technol. 2018, 255, 234–241. [Google Scholar] [CrossRef]
- Luo, J.; Wang, X.; Zhao, G.; Wang, J. Study on mechanical properties and microstructure of gradient functional layer prepared by CO2 surfacing welding with electromagnetic stir. Acta Metall. Sin. 2009, 45, 1–10. [Google Scholar]
- Abachi, S.; Akkök, M.; Gökler, M.İ. Wear analysis of hot forging dies. Tribol. Int. 2010, 43, 467–473. [Google Scholar] [CrossRef]
- Davoudi, M.; Farokhi Nejad, A.; Rahimian Koloor, S.S.; Petrů, M. Investigation of effective geometrical parameters on wear of hot forging die. J. Mater. Res. Technol. 2021, 15, 5221–5231. [Google Scholar] [CrossRef]
- Emamverdian, A.A.; Sun, Y.; Cao, C.; Pruncu, C.; Wang, Y. Current failure mechanisms and treatment methods of hot forging tools (dies)—A review. Eng. Fail. Anal. 2021, 129, 105678. [Google Scholar] [CrossRef]
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Turek, J.; Cieślik, J. A Review of Methods for Increasing the Durability of Hot Forging Tools. Materials 2025, 18, 3669. https://doi.org/10.3390/ma18153669
Turek J, Cieślik J. A Review of Methods for Increasing the Durability of Hot Forging Tools. Materials. 2025; 18(15):3669. https://doi.org/10.3390/ma18153669
Chicago/Turabian StyleTurek, Jan, and Jacek Cieślik. 2025. "A Review of Methods for Increasing the Durability of Hot Forging Tools" Materials 18, no. 15: 3669. https://doi.org/10.3390/ma18153669
APA StyleTurek, J., & Cieślik, J. (2025). A Review of Methods for Increasing the Durability of Hot Forging Tools. Materials, 18(15), 3669. https://doi.org/10.3390/ma18153669