Authors:
Faraz Deirmina (1), Lorenzo Quarzago (2), Eleonora Bettini (1), Matthew Ritche (3), Daniel Butcher (3), Shahin Mehraban (3), Nicholas Lavery (3), Massimo Pellizzari (2)
1- Powder R&D Group, Sandvik Additive Manufacturing, Sweden
2- University of Trento, Dept. of Industrial Engineering, Italy
3- Swansea University, MACH1 Laboratories, Dept. of Mechanical Engineering, United Kingdom
Abstract:
Hot work tool steels with medium C contents are known to be difficult to process by laser powder bed fusion (L-PBF). Cold and, to a lesser extent, hot cracking occurs in these alloys. Cold cracks are attributed to the low ductility and large residual stresses due to the complex thermal profiles. These can be avoided by platform preheating, which may introduce additional costs and side-effects on microstructure and properties. Therefore, the market trend is to develop new steel grades with improved 3D-printabilty. In this work, a prototype alloy with a leaner C content is proposed. To compensate for the negative effect of reduced C, computational thermodynamics was used to define chemistries with an optimized balance of carbide forming elements, and Si. The prototype tool steel shows enhanced L-PBF processability, and properties meeting and/or exceeding those of wrought AISI H13 in terms of hot strength, tempering and thermal fatigue resistance.
DOI:
https://doi.org/10.59499/EP235765264