Compositionally graded nano-sized borides in a directionally solidified nickel-base superalloy

被引：8

作者：

Gupta, Richa ^{[1
]}

Kumar, K. C. Hari ^{[2
]}

Prasad, M. J. N. V. ^{[1
]}

Pant, Prita ^{[1
]}

机构：

[1] Indian Inst Technol, Dept Met Engn & Mat Sci, Mumbai 400076, Maharashtra, India

[2] Indian Inst Technol Madras, Dept Met & Mat Engn, Chennai 600036, Tamil Nadu, India

来源：

SCRIPTA MATERIALIA | 2021年 / 201卷

关键词：

Ni-base superalloy; Boron; Nano-precipitates; Scanning/transmission electron microscopy (STEM); Secondary ion mass spectroscopy (SIMS); ELECTRON-MICROSCOPY; GRAIN-BOUNDARIES; BORON; MICROSTRUCTURE; EVOLUTION; PRECIPITATION; ADDITIONS; ASTROLOY; CREEP; PHASE;

D O I：

10.1016/j.scriptamat.2021.113981

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Boron is known to influence the grain boundary microchemistry and thereby improve the mechanical performance of superalloys; however, the form in which boron exists at the grain boundary is debatable. We show from electron microscopy characterization that in a directionally solidified Ni-base superalloy boron is present in the form of nearly spherical nano-sized metal borides. We also report the existence of a gradient in composition of Cr, and W within the nano-sized boride precipitates located along the grain boundaries. These borides are present discretely and suppress the agglomeration of mostly reported M23C6 carbides at the columnar grain boundaries. This could be a possible reason for the reported improvement in transverse creep properties of boron modified directionally solidified superalloys. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页数：5

共 33 条

[1] Atomic-scale APFIM and TEM investigation of grain boundary microchemistry in astroloy nickel base superalloys [J].

Blavette, D ;

Duval, P ;

Letellier, L ;

Guttmann, M .

ACTA MATERIALIA, 1996, 44 (12) :4995-5005

[2]

Bouse G.K., 2008, P INT S SUP, V11, P99

[3]

Brandon D., 2008, MICROSTRUCTURAL CHAR

[4] Atom probe tomography investigation of the microstructure of superalloys N18 [J].

Cadel, E ;

Lemarchand, D ;

Chambreland, S ;

Blavette, D .

ACTA MATERIALIA, 2002, 50 (05) :957-966

[5] The microstructures of base/modified RR2072 SX superalloys and their effects on creep properties at elevated temperatures [J].

Chen, QZ ;

Jones, N ;

Knowles, DM .

ACTA MATERIALIA, 2002, 50 (05) :1095-1112

[6] Microstructure of Carbides at Grain Boundaries in Nickel Based Superalloys [J].

Dong, Xiaoming ;

Zhang, Xiaoli ;

Du, Kui ;

Zhou, Yizhou ;

Jin, Tao ;

Ye, Hengqiang .

JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY, 2012, 28 (11) :1031-1038

[7] Precipitation and evolution of grain boundary boride in a nickel-based superalloy during thermal exposure [J].

Du, Beining ;

Sheng, Liyuan ;

Cui, Chuanyong ;

Yang, Jinxia ;

Sun, Xiaofeng .

MATERIALS CHARACTERIZATION, 2017, 128 :109-114

[8] The Wyckoff positional order and polyhedral intergrowth in the M3B2- and M5B3-type boride precipitated in the Ni-based superalloys [J].

Hu, X. B. ;

Zhu, Y. L. ;

Sheng, N. C. ;

Ma, X. L. .

SCIENTIFIC REPORTS, 2014, 4

[9] Crystallographic account of nano-scaled intergrowth of M2B-type borides in nickel-based superalloys [J].

Hu, X. B. ;

Zhu, Y. L. ;

Ma, X. L. .

ACTA MATERIALIA, 2014, 68 :70-81

[10] The effect of grain boundary segregation of boron in cast alloy 718 on HAZ microfissuring - A SIMS analysis [J].

Huang, X ;

Chaturvedi, MC ;

Richards, NL ;

Jackman, J .

ACTA MATERIALIA, 1997, 45 (08) :3095-3107

← 1 2 3 4 →