Fe–Al–Cr heat resistant sinters

Preparation, structure and properties of heat resistant Fe–Al–Cr sinters have been analysed. Sinters were prepared from a mixture of Fe–Al, Fe and Cr powders, uniaxially pressed and sintered in a temperature 1448 K (1175°C), a time ranging from 5–600 min, and in a vacuum of 10−4 Pa. The sinters produced were subjected to the following tests: metallographic, X-ray analysis, X-ray microanalysis and the high temperature oxidation resistance. Fe–Al–Cr sinters consists of diffusive aluminised and chromed iron particles nad fine Al2O3 and/or Cr2O3 oxides. They have porosity below 6%. The relations between chemical contents of sinters as well as the parameters of the sintering process, structure and properties of sinters have been defined. The Fe–Al–Cr sinters have approximately as good oxidation resistance as non-porous Fe–Al–Cr alloys. A specific feature of oxidation Fe–Al–Cr sinters is filling of sinter pores by oxidation product in the initial period of the process. As a result of this process a Fe–Al–Cr sinters occurs similar behaviour to non-porous alloys during further stages of oxidation.