Study the Impact of Chromium and Yttrium Oxide on the Mechanical Characteristics of Nial Alloy Used in Aircraft Engines

The present investigation has been performed at 1350°C for 90 min under the atmosphere of argon gas with a nickel aluminide NIAl composite enhanced with yttrium Y2O3 and additional chromium. Brinell hardness according to (ASTM E140 – 12b) was performed. By adding 1.5 wt. % Cr, the compound hardness (90NiAl-10Y2O3) is increased to 290 HB and continues to expand to 373 HB by additivity of 2.5 wt. % Cr to NiAl. The hardness increases to 390 HB for the compound content (70NiAl-30Y2O3) by adding 1.5 wt. % Cr, and continues to develop by adding 2 wt. % Cr to around 406 HB. By the addition of 2.5 wt. % Cr, the hardness increases to 438 HB. The wear test results exposed that the additional cobalt leads to reduce the wear-rate of NiAl- 30Y2O3. Addition of 1.5 wt. % Cr leads to reduce the adhesion wear rate from 7.61 * 10-6 gr/cm to 7.49 * 10-6 gr/cm while adding 2 wt. % of Cr decreases the wear rate to 6.46* 10-6 gr /cm. By the addition of 2.5 wt. % Cr, the wear rate decrease to 5.84 * 10-6 gr/cm.