IMPACT OF CARBON ON THE STRUCTURE AND THERMAL PROPERTIES OF NEW CARBON SUPERINVAR ALLOYS

  • Alexander Sergeevich Zhilin
  • Sergey Vladimirovich Grachev
  • Mikhail Aleksandrovich Filippov
  • Svetlana Mikhailovna Nikiforova
  • Alain Igorivna Purgina

Abstract

Super-invar alloys based on Fe-Ni-Co with additions of carbon in wide range (0,6%, 0,8% and 1,7% С) have been investigated. Metallography analysis showed that graphite phase distributed throughout the volume of alloy in a fine state. Moreover, the size of graphite inclusions rises with the increasing of the total contents of carbon. It is showed, that after a heat treatment the morphology of graphite phases may change. Thermal analysis revealed that it is necessary to up the temperature of annealing unto 800°С because at that temperature the graphitization processes proceeds more fully. It is also showed that after annealing (800°С, 3h) investigated alloys induce minimal thermal expansion (a20-100 < 1,5×10-6К-1).
Section
Technical Sciences