Metal Additive Manufacturing Conference 2019

It has been hypothesized that the design flexibility offered by additive manufacturing (AM) can be beneficially employed to improve tool life and part quality in high pressure die casting (HPDC) applications, particularly, to address challenges originating from inadequate temperature management. The principle challenge in terms of adapting the AM technology in these applications though is the lack of availability of tool steel materials with properties suitable for the demanding HPDC conditions together with the necessary “printability”. In this work, the characteristics of a newly developed AM tool steel- Uddeholm AM Heatvar optimized for utilization in HPDC applications are discussed. The processing of the alloy with regard to both printing and subsequent post treatment suitable for the application demands is presented. It is shown that the aforementioned tool steel along with good processability in Laser Powder Bed Fusion (LPBF), exhibits excellent hot-strength and temper-back resistance at elevated temperatures relevant for HPDC. It is also shown that the “resistance to soldering”, soldering being a wear mechanism by chemical corrosion-interaction between the tool surface and the melt, for Uddeholm AM Heatvar is comparable to that of conventionally used H13 type alloys and is superior to commercially available AM steel grades. The compatibility of the developed tool steel in terms of being able to be “printed” on existing tool steel base materials, so called “hybrids”, is also discussed. The performance of the new AM tool steel grade is elucidated using a case study.