Authors:
Pelle Mellin (1), Johannes Gårdstam (2), Stefan Heino (1), James Shipley (2), Anders Magnusson (2), Fredrik Forsberg (3), Björn Forsgren (4), Per Waernqvist (4)
1- Swerim AB, Kista, Sweden
2- Quintus Technologies AB, Västerås, Sweden
3- Luleå University of Technology, Luleå, Sweden
4- Ringhals AB, Väröbacka, Sweden
Abstract:
Pores in cast, compacted or AM built material that shrink during HIP, can regrow if they are filled with argon and are subjected to high temperature. To better understand this, we present a study on a set of capsules that contain a huge 2 cm3 cavity. These cavities were filled with argon by sealing them under 1 atm of 100% argon. Using HIP (equipped with URQ) these cavities shrink to an approximate size of 0.006 cm3 resulting in a room temperature pressure of ~340 bars. Upon stepwise reheating the pressure increases, and for IN718 the cavity expands above 900 °C (pressure is here ~1400 bar), while for 316L the cavity expands above 1000 °C (pressure is here ~1450 bar). The temperature at which expansion occurs are not far from typical HIP conditions, which makes sense. The pressure inside a pore appears to be a good indicator for if expansion will occur.
DOI:
https://doi.org/10.59499/EP246280783
