Directional solidification of Ni base superalloy IN738LC to improve creep properties

2000 ◽  
Vol 16 (5) ◽  
pp. 579-586 ◽  
Author(s):  
A. Kermanpur ◽  
N. Varahraam ◽  
E. Engilehei ◽  
M. Mohammadzadeh ◽  
P. Davami
Keyword(s):  
Directional Solidification ◽  
Creep Properties ◽  
Superalloy In738lc ◽  
Base Superalloy

Microstructure Evolution with Solidification Rates in IN 738LC Superalloy

2006 ◽  
Vol 510-511 ◽  
pp. 450-453 ◽  
Author(s):  
H.C. Kim ◽  
Y.H. Kim ◽  
Yeon Gil Jung ◽  
Je Hyun Lee ◽  
Chang Yong Jo ◽  
...  
Keyword(s):  
Directional Solidification ◽  
Morphological Evolution ◽  
Solidification Rate ◽  
Planar Interface ◽  
Interface Morphology ◽  
High Thermal Gradient ◽  
Solid Liquid Interface ◽  
Superalloy In738lc ◽  
Solid Liquid ◽  
Base Superalloy

The morphological evolution and growth mechanism of solidification interface with solidification rates were investigated in the Ni-base superalloy, IN738LC, by directional solidification and quenching technique under a relatively high thermal gradient of 20.5oC/mm. The planar interface of the MC-γ eutectic was found at the low solidification of 1 µm/s, and the dendritic interface formed above 5 µm/s. The dendrite lengths increased as increasing increasing solidification rate, and the dendrite tip temperature was close to the liquidus temperature at 50 µm/s. The carbide morphologies were blocky-type and rod-type in the planar interface of low solidification rates, and as the solidification rate increased, the carbide shape changed from script type to spotty type. The phase transformation temperatures from the dendrite to MC carbide and eutectic were estimated by DTA and by the solid/liquid interface morphology by directional solidification.

scholarly journals A Phenomenological Analysis of Freckling in Directional Solidification of Ni-Base Superalloy: The Role of Edge and Curvature in Casting Components

2019 ◽  
Vol 51 (1) ◽  
pp. 88-92 ◽  
Author(s):  
D. X. Ma ◽  
Z. H. Dong ◽  
F. Wang ◽  
H. B. Dong
Keyword(s):  
Directional Solidification ◽  
Positive Curvature ◽  
Phenomenological Analysis ◽  
Geometrical Factor ◽  
Freckle Formation ◽  
Base Superalloy

Abstract The geometrical factor in freckle formation has rarely been taken into account. In this work, freckle formation in superalloy components is examined. It is found that freckle formation is subject to the effects of the edge and curvature. In polygonal casting sections, freckles are formed preferably on the convex edges. In the components with a curved contour, freckles are exclusively formed on the outward-curving surface having positive curvature.

scholarly journals Effects of Phosphorus on Creep Properties of Nickel-Iron Base Superalloy

2015 ◽  
Vol 55 (5) ◽  
pp. 1100-1105 ◽  
Author(s):  
Koichi Takasawa ◽  
Hibiki Chinen ◽  
Takuya Ohkawa ◽  
Eiji Maeda ◽  
Takashi Hatano
Keyword(s):  
Creep Properties ◽  
Nickel Iron ◽  
Iron Base ◽  
Base Superalloy

scholarly journals Microstructure and Creep Properties of Ni-Base Superalloy IN718 Built up by Selective Laser Melting in a Vacuum Environment

Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 362 ◽  
Author(s):  
Toshiki Nagahari ◽  
Taigi Nagoya ◽  
Koji Kakehi ◽  
Naoko Sato ◽  
Shizuka Nakano
Keyword(s):  
Selective Laser Melting ◽  
Titanium Oxides ◽  
Laser Melting ◽  
Creep Life ◽  
Creep Properties ◽  
New Process ◽  
Δ Phase ◽  
Brittle Fractures ◽  
The Stability ◽  
Base Superalloy

Selective laser melting (SLM) in a vacuum environment is a relatively new process. Although the material is expected to undergo a gradual heat change, which will influence the microstructure and creep properties of IN718, little research has been conducted to date. Here, we compared specimens built in vacuum (V-SLM) to those built in an Ar atmosphere (Ar-SLM). We investigated the microstructure and creep properties of V-SLM, and compared the V-SLM specimen to a conventional Ar-SLM specimen. The V-SLM specimen had a larger-grained texture, and the quantity of the δ phase was much lower. In addition, the V-SLM specimen had lower amounts of aluminum and titanium oxides, which improved the stability of the γ″ phase. Thus, the V-SLM specimen showed better creep life than the Ar-SLM, due to prevention of brittle fractures along the interdendritic regions.

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