New P/M Fe-Cr-Al alloy with excellent hot strength

P/M heating alloy containing 23%Cr-5%Al was produced by Gas-Atomization and HIP process. The microstructures and the hot strength of this alloy were investigated in comparison with conventionally cast and forged alloy. A uniform distribution of small precipitates and a fine grained structure were found in an annealed state. It was also found that secondary recrystallization took place after a time at a high temperature, resulting in an extremely large grained structure. Excellent hot strength due to the large grained structure was confirmed by a hot tensile test and a practical test in our HIP furnace.