Abstract:This review summarizes the main research results of the studies on high temperature structural intermetallic NiAl and its alloys, Ni₃Al and its alloys, FeAl and its alloys, Fe₃Al and its alloys,  TiAl alloys,  and environmental
embrittlement in intermetallics in the research group of superallloys and intermetallics (the author’s group) in the past 20 years since 1988. This paper introduces discovery of the superplasticity and its mechanisms of the NiAl alloys, selective addition of rare earth to significantly improve room temperature ductility and high temperature oxidation resistance of NiAl alloys, Brittle to ductile transition (BDT) and its mechanisms of the NiAl alloys, mechanisms of strengthening and toughening of nanocrystalline NiAl and its nanocomposites, in-situ particle-reinforced NiAl composites and mechanisms of strengthening and toughening, discovery of excellent high temperature friction and wear property of NiAl alloy and self-lubrication mechanism, effect of alloying element and development of JJ-3 alloy, discovery of selective addition of Zr to improve ductility of B-free Ni₃Al alloys firstly in the world, discovery of improvement of strengthening and toughening of Ni₃Al with addition of B content to around solubility, discovery of anomalous yield peak in FeAl alloys and its mechanism, selective addition of Mg to significantly improve room temperature ductility and its mechanism, the microstructure, phase transition and interface microstructure of TiAl-W-Si alloy, discovery of environmental embrittlement of intermetallics with its essence being hydrogen induced embrittlement, and investigation of environmental embrittlement and its mechanism of L1₂ -type Co₃Ti alloy with first principle method DVM firstly in the world.

Key words: intermetallics; NiAl; Ni₃Al; FeAl; Fe₃Al; TiAl alloys, environmental embrittlement