Document Type : Original Reaearch Article

Authors

Department of Materials Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

Inconel 718 is precipitation strengthened Ni-base superalloy that is strengthened by γ″ precipitate with the Ni3Nb chemical composition, widely used for medium and high temperature applications in different industries. Despite high resistance to strain aging cracking for Inconel 718, this alloy is more sensitive to solidification and liquation cracking. The main purpose of this investigation is to compare the effect of Nd:YAG pulsed laser and fiber continuous laser on  the Microstructure, Connection Geometry and Hot cracking Mechanism in Inconel 718.  For this purpose, an Nd: YAG pulsed laser device and a continuous wave fiber laser device were used. To determine the percentage of the elements, using the quantum test and an electron microscope and optical microscope (OM) was used to investigate the microstructure and electron microscopy (SEM) equipped with EDS also used for chemical analysis.

Keywords

 
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