Abstract:Two kinds of aluminum-based abradable seal coatings (AlSi-hBN and AlSi-PHB) were prepared by atmospheric plasma spraying. XRD, OM, SEM, quasi-static and dynamic compression tests were utilized to research the microstructure, compressive properties under different strain rates and relevant damage characteristics of the seal coatings. The results indicated that AlSi-hBN and AlSi-PHB seal coatings were mainly composed of α-Al solid solution phase, eutectic Si phase, abradable second phase (hBN/PHB) and pores. No obvious yield platform was observed on compressive true stress-true strain curves of two coatings under both quasi-static and dynamic loading conditions. The dynamic compressive strength of AlSi-hBN coating was higher than that of AlSi-PHB coating. Particles inside the coatings were severely deformed under dynamic loading. The main damage forms were debonding and cracking at the interparticle interface as well as initiation and propagation of cracks at the internal defects.