Powder bed fusion employing the electron beam distinguishes itself as an excellent method to process crack-susceptible, high-performance alloys and metals, such as ni-base superalloys, TiAl and tungsten. This capability is mainly due to the high operating temperatures enabled by the powerful and flexible electron beam, which helps to mitigate thermal gradients and reduce the corresponding mechanical stresses. To achieve these high operating temperatures, a regular process cycle often includes multiple heating steps, which account for a significant fraction of the total layer time. Consequently, controlling the emerging thermal conditions is a key factor for efficient process management and obtaining optimal results. In order to resolve and comprehend the prevalent thermal conditions, a GPU-parallelised, in-house developed model is presented, which depicts the thermal evolution of entire build volumes over multiple layers in a scan-resolved manner. The ability to reconstruct the process as a digital twin opens the possibility of analysing the different process steps in detail and addressing possible shortcomings effectively. An application of this method is provided with the processing of tungsten. The extraordinary material properties, including very high thermal conductivity and a exceptional high liquidus temperature, impose great challenges regarding the efficiency of energy input and the scaling to large components [1]. By analysing the conditions of a current experimental process setup, specific improvements and new strategies are derived with the ultimate goal of increasing overall productivity. REFERENCES [1] Talignani A, Seede R, Whitt A, Zheng S, Ye J, Karaman I, et al. A review on additive manufacturing of refractory tungsten and tungsten alloys. Additive Manufacturing (2022) 58:103009