Effect of heat treatment on mechanical properties, solidification structure and segregation of Inconel 625 alloy in additive manufacturing process by DLMD method

Subject Areas :

mohammad  gavahian jahromi ¹ (Malek Ashtar University of Technology, Iran.)
Reza  Shoja Razavi ² (Professor of Materials Science and Engineering, Faculty of Materials and Manufacturing Technologies, Malekashtar University of Technology, Tehran, 16788-15611,)
hamed  Naderi ³ (Malek Ashtar University of Technology, Iran.)
fareed  kermani ⁴ (Malek Ashtar University of Technology, Iran.)

Received: 2023-03-14 Accepted : 2024-06-19 Published : 2024-03-04

Keywords: IN625 , Additive manufacturing, DLMD method, Segregation, Homogenization,

Abstract :

Direct metal laser deposition is using for rebuilding and manufacturing parts. In this method, it is imperative to check the melting and solidification conditions. In this research the effect of the primary process parameters on the microstructure has been investigated. Distance of the dendritic arms, and the segregation of alloy elements, to determine the mechanical properties of IN625. According to the examination of the scanning electron microscope image, by moving from the interface to the top of the cladding. The solidification structure changed from columnar dendritic to coaxial dendritic with decreased G/R ratio. From the interface to the sample’s surface, the cooling rate increased, and the spread between the dendritic arms decreased. By moving away from the interface, the distance of the dendritic arm increases. By changing the laser power from 250 to 450 watts, the G/R ratio decreased from 1252.08 ℃/〖mm〗^2 to 970.34℃/〖mm〗^2 . It was conducting heat treatment led to the uniformity of alloy elements in the background phase. Also, with heat treatment, tensile strength, and elongation increased and yield strength decreased.