PM-HIP Development and Production of Large Nuclear Components -- A Review

PM-HIP Development and Production of Large Nuclear Components

1. Gandy, M. Albert, S. Tate, B. Sutton (EPRI)
2. Samarov (Synertech-PM)

Multiple advanced manufacturing options are available to industry to assist in manufacture, fabrication, and installation of both small modular reactors (SMRs) and advanced reactors (ARs). These include, but are not limited to, directed energy deposition additive manufacturing, powder bed additive manufacturing, electron beam welding, cold spray welding/deposition, diode laser cladding, and powder metallurgy-hot isostatic pressing (PM-HIP). Over the past four years, EPRI (under US DOE DE-NE0008629), has been exploring the use of PM-HIP to produce large, low alloy steel, reactor pressure vessel components at 2/3rds-scale. In this research, EPRI and Synertech-PM have been able to demonstrate that very large components (RPV upper and lower heads, steam plenum nozzles, transition shell sections, and valve bodies) can be readily produced to near-net shape. Furthermore, this research has shown that excellent tensile properties can readily be achieved for these components. However, to date the researchers have been unable to demonstrate acceptable toughness properties at scale due in part to incoming powder quality and processing methods employed. This paper will describe the EPRI/DOE research to date and describe some of the alternatives that are being explored to improve final component toughness characteristics.