INVESTIGATION OF MICROSTRUCTURE AND MICROHARDNESS PROPERTIES OF CO AND CR REINFORCED NIAL INTERMETALLIC COMPOUND PRODUCED BY SHS METHOD

Abstract

In this study, the porous samples were manufactured through selfpropagatinghigh-temperature synthesis (SHS) by adding 10 % Co and Cr to50 % Ni – 50 % Al powders. 10 % Co and Cr added 50 % Ni – 50 % Alsamples were mixed for 12 hours using a mixer with a rotational speed of300 rpm and compacted under 100 MPa pressure. The obtained sampleswere then synthesized by moving them to an argon atmosphere andcombusted with the aid of a tungsten electrode. The obtained samples afterthe combustion reaction were characterized in terms of their microstructureusing scanning electron microscope - the backscattered electrons (SEMBSE).The elemental and phase analysis were carried out using EDS andXRD, respectively. The Energy-dispersive spectroscopy (EDS) resultsshowed that the dominant element was Ni and the presence of Co with Crwas less than that of Al. As a result of XRD analyses, it was determined thatNiAl was formed as the dominant phase in the samples and also Ni3Al andNiAl3 phases were formed in low amounts. Both Cr and Co additionincreased hardness of NiAl alloy. However, Cr has a greater effect on theincrease of hardness values than Co.