Charpy impact properties of pure tungsten plate material in as-received and recrystallized condition (1 h at 2000 °C (2273 K))

The aim of this paper is to assess the fracture behavior of tungsten plate material. Plate material with a thickness of 1 mm and 4 mm was investigated, considering samples with dimensions of 1 × 3 × 27 mm3 without notch, 3 × 3 × 27 mm3 without notch, and 3 × 4 × 27 mm3 with a 1 mm notch (KLST). The plate material was in either as-received or recrystallized condition (annealed for 1 h at 2000 °C (2273 K)). All samples were characterized by means of Charpy impact tests, which were performed up to 1000 °C (1273 K) in a vacuum. The results show that plate material is anisotropic and that the brittle-to-ductile transition temperature (BDTT) strongly depends on the orientation of the specimen. A comparison of the results of notched and unnotched samples shows that delamination behavior only appears on notched samples and that unnotched samples show the classical brittle-to-ductile transition (BDT). Furthermore, it is shown that recrystallized tungsten plate material is extremely brittle and that the BDT does not even appear at a test temperature of 1000 °C (1273 K).