THE EFFECT OF CHANGES IN THE AMOUNT OF CO ELEMENT ON THE MECHANICAL PROPERTIES OF DIRECTIONALLY SOLIDIFIED AL–5.7 WT % NI–X WT % CO ALLOYS


Bayram Ü.

SİVAS - INTERNATIONAL CONFERENCE ON SCIENTIFIC AND INNOVATION RESEARCH, Sivas, Turkey, 13 - 15 October 2022, pp.36

  • Publication Type: Conference Paper / Summary Text
  • City: Sivas
  • Country: Turkey
  • Page Numbers: pp.36
  • Abdullah Gül University Affiliated: Yes

Abstract

In this study, Al–5.7 wt % Ni– X wt % Co (X=0.02, 0,05, and 0.5) alloys were prepared using metals of Al (>99.95%), Ni (>99.99%), and Co (>99.99%) in the vacuum atmosphere. Directional solidification experiments of Al–Ni–Co alloys which have industrial and scientific interests due to their mechanical properties, were implemented by using Bridgman-type directional solidification apparatus (BTDSA) at a constant growth rate (8.25 μm s-1) and different temperature gradients (5.12, 5.95, 6.71 K mm-1). The effect of changes in the amount of Co element on the mechanical properties (microhardness (HV) and tensile strength (σ)) and microstructure of the alloy was investigated. X-ray diffraction (XRD) was used to characterize all phases forming the alloy. The microstructures of the samples were photographed with an Olympus BHX type light optical microscope (Integrated Olympus DP12 digital camera) because the alloy’s phases were directly visible for each alloy. Microhardness measurements in the present work were performed with a Future-Tech FM-700 model microhardness device and the tensile strength values of alloys were measured at room temperature with a Shimadzu Universal Testing Instrument (Type AG-10 KNG) at a frequency of 10–3. According to experimental results, it was observed that the increase in the Co element caused more irregularity in the microstructure of the alloy and the orientation of the phases in different directions. In addition, the microhardness and tensile strength values increased with the increase of the Co element. All results obtained in the present work were compared with the Al−based similar experimental results in the literature.