{"id":48499,"date":"2025-10-28T10:41:34","date_gmt":"2025-10-28T09:41:34","guid":{"rendered":"https:\/\/www.bonomiacciai.it\/resistenza-alla-fatica-termica-lanalisi-tecnica-del-thermodur-e40k-superclean\/"},"modified":"2025-10-30T08:18:34","modified_gmt":"2025-10-30T07:18:34","slug":"resistenza-alla-fatica-termica-lanalisi-tecnica-del-thermodur-e40k-superclean","status":"publish","type":"post","link":"https:\/\/www.bonomiacciai.it\/en\/resistenza-alla-fatica-termica-lanalisi-tecnica-del-thermodur-e40k-superclean\/","title":{"rendered":"Thermal Fatigue Resistance: The Technical Analysis of Thermodur\u00ae E40K Superclean"},"content":{"rendered":"
[vc_row][vc_column][vc_column_text css=””]In the die casting sector, die failure is an operational cost and a critical process interruption. The main cause is well-known: 80% of failures are due to thermal fatigue. To meet this challenge, the hot work tool steel Thermodur E40K Superclean was developed. Bonomi Acciai, through our technicians E. Prati and A. Magistrelli, managed the publication of the technical analysis of this material in the prestigious journal “La Metallurgia Italiana,” the official publication of the Italian Association for Metallurgy (AIM). This in-depth article analyzes the data from that paper, demonstrating why this steel represents a fundamental evolution for die lifespan.[\/vc_column_text][\/vc_column][\/vc_row][vc_row][vc_column]
\"L'articolo<\/div><\/figure>[\/vc_column][\/vc_row][vc_row][vc_column][vc_column_text css=”” text_align=”center”]\n

The technical article curated by our engineers, published in the May 2020 issue of “La Metallurgia Italiana”, the official journal of the Italian Association for Metallurgy (AIM).<\/p>\n

Click here to download the full PDF of the article.<\/a><\/strong><\/p>\n[\/vc_column_text][\/vc_column][\/vc_row][vc_row][vc_column]

<\/div>[\/vc_column][\/vc_row][vc_row][vc_column][vc_custom_heading text=”The Problem: Failure due to Thermal Shock” use_theme_fonts=”yes” css=””][vc_empty_space height=”16px”][vc_column_text css=””]Die casting dies undergo extreme cyclic stress: the cavity surface is rapidly heated by the injection of the molten alloy and then cooled. This continuous expansion and contraction generate a network of micro-cracks, known as heat checking or thermal fatigue, which inevitably grow until they cause failure. While other factors like stress cracking (9%) or corrosion (7%) have an impact, thermal fatigue resistance remains the critical parameter for a die’s service life.[\/vc_column_text][\/vc_column][\/vc_row][vc_row][vc_column]
<\/div>[\/vc_column][\/vc_row][vc_row][vc_column][vc_custom_heading text=”The Solution: Thermodur E40K Superclean” use_theme_fonts=”yes” css=””][vc_empty_space height=”16px”][vc_column_text css=””]Thermodur E40K Superclean was developed by Deutsche Edelstahlwerke (part of Swiss Steel Group) specifically to maximize thermal fatigue resistance, combined with high toughness and wear resistance at high temperatures. It is an Electro-Slag Remelted (ESR) steel<\/b>, featuring a homogeneous microstructure and a low Silicon content to improve toughness. It also complies with the rigorous standards of the NADCA #207<\/b> specification.<\/p>\n

To validate its performance, the material was compared with standard industry steels: H11<\/b> and H13<\/b>.[\/vc_column_text][\/vc_column][\/vc_row][vc_row][vc_column]

<\/div>[\/vc_column][\/vc_row][vc_row][vc_column][vc_custom_heading text=”Data Analysis: Proof of Technical Superiority” use_theme_fonts=”yes” css=””][vc_empty_space height=”16px”][vc_column_text css=””]\n
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The laboratory tests, presented in the article, focused not only on hardness but on the properties that truly determine a die’s life.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n[\/vc_column_text][\/vc_column][\/vc_row][vc_row][vc_column][vc_custom_heading text=”1. The Critical Test: The Thermal Fatigue Test” use_theme_fonts=”yes” css=””][vc_empty_space height=”16px”][vc_column_text css=””]\n

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To simulate operating conditions, samples of the different steels (quenched and tempered to 45\u00b11 HRC) were subjected to thousands of thermal cycles: induction heated to 650\u00b0C<\/b> and immediately quenched in 60\u00b0C<\/b> water. The results are unequivocal:<\/p>\n