Finite element simulation and microstructure analysis of nickel based alloy for additive manufacturing

• Published in: MATEC Web of Conferences Vol. 242; p. 1022
• Main Authors: Heping, Liu, Fenger, Sun, Fenger, Yibo, Shaolei, Cheng, Bin, Liu
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Les Ulis EDP Sciences 01.01.2018
• Subjects: Cracks; Finite element method; Heat resistant alloys; Isotherms; Laser beam melting; Lasers; Mechanical properties; Microstructure; Nickel base alloys; Rapid prototyping; Stress concentration; Substrates; Superalloys; Temperature distribution; Widmanstatten structure
• ISSN: 2261-236X; 2274-7214; 2261-236X
• DOI: 10.1051/matecconf/201824201022

In this paper, the finite element simulation of GH4169 high temperature alloy by selective laser melting was carried out, and the microstructure was analyzed by experiments. The results show that the shape of the temperature field cloud formed by the laser heat source is different from the shape of the theoretical model, but is in the shape of the ellipse. The temperature gradient at the front end of the molten pool is larger than that of the back end of the molten pool, and the isotherm of the front end of the molten pool is more intensive. The temperature of the substrate is less affected by the temperature gradient. The temperature gradient of the front end of the melting pool is larger than the back end of the molten pool, and the temperature field of selective laser melting is like a meteor with trailing tail. In the laser heat source, the temperature isotherm is the most dense and the temperature gradient is maximum. The relative effect of mechanical properties of δ phase is very complex. When the phase is precipitated by widmanstatten structure, it is easy to produce stress concentration as a source of cracks