A Comparative Study of Directed Energy Deposition-Arc and Casting: Enhancing Mechanical and Thermal Properties of Hot-Work Tool Steels

Abstract

Additive manufacturing using directed energy deposition-arc (DED-Arc/M) offers an efficient method for producing complex, medium-sized parts with minimal material waste. This makes it particularly attractive for rapid and cost-effective tool production for hot-working applications such as injection molding, die casting, hot-stamping, and forging. However, the rapid cooling and repeated thermal cycling during DED-Arc/M lead to microstructures that differ significantly from those in conventionally cast materials. While the mechanical properties of additively manufactured tool steels are well-documented, their thermophysical properties remain insufficiently studied. Thus, this work investigates the effects of DED-Arc/M processing on both mechanical and thermophysical properties of the hot-work tool steel AISI H13 (X40CrMoV5-1), in comparison to conventionally cast material. A novel statistical approach applies the Gini coefficient to quantitative EDS data to assess the homogeneity of alloying elements. The mechanical properties at elevated temperatures are evaluated through hardness, tensile, and compression testing, while thermal conductivity is measured between 50 and 500 °C. The results provide a comprehensive understanding of how DED-Arc/M influences microstructure and material performance. Overall, the findings highlight DED-Arc/M as a promising technology for manufacturing efficient, high-performance tools for hot-working applications.