INVESTIGATION OF GAMMA/GAMMA' LATTICE MISMATCH IN THE POLYCRYSTALLINE NICKEL-BASE SUPERALLOY IN738LC - INFLUENCE OF HEAT-TREATMENT AND CREEP DEFORMATION

被引：81
作者：
LI, J
WAHI, RP
机构：
[1] Hahn-Meitner-Institut Berlin GmbH, 14109 W-Berlin
来源：
ACTA METALLURGICA ET MATERIALIA | 1995年 / 43卷 / 02期
关键词：
D O I：
10.1016/0956-7151(94)00252-D
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
The gamma/gamma' lattice misfit in the polycrystalline nickel-base superalloy IN738LC has been determined by convergent beam electron diffraction (CBED) technique in a transmission electron microscope (TEM). The influence of heat treatment and creep deformation on the misfit was investigated. The chemical compositions of the gamma and gamma' phases were analysed with the help of Energy Dispersive Spectrometry (EDS). The influence of different heat treatments on the gamma/gamma' misfit can be explained in terms of the dependence of the chemical compositions of gamma and gamma' phases on the heat treatments. The creep deformation causes a tetragonal distortion in gamma' precipitates and leads to considerable changes in the misfit. The tetragonality in gamma' phase and the evolution of the misfit during creep process can be understood on the basis of a dislocation model. An estimation of the local internal stress in gamma' phase generated by gamma/gamma' interfacial dislocations formed during creep deformation shows it to be higher than the applied stress.
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页码：507 / 517
页数：11
相关论文
共 51 条
[1]  
AYRAULT D, 1987, ADV MATER PROCESS, P71
[2]  
BALDAN A, 1992, SUPERALLOYS 1992, P647
[3]  
BIERMANN H, 1991, 9TH P INT C STRENGTH, P421
[4]   ON THE EFFECTS OF HEAT-TREATMENTS ON THE CREEP-BEHAVIOR OF A SINGLE-CRYSTAL SUPERALLOY [J].
CARON, P ;
HENDERSON, PJ ;
KHAN, T ;
MCLEAN, M .
SCRIPTA METALLURGICA, 1986, 20 (06) :875-880
[5]  
CARPENTER GJC, PHILIPS ELECTRON OPT, V125, P16
[6]  
CLIFF G, 1972, 5TH P EUR C EL MICR, P140
[7]  
DIETER GE, 1976, MECHANICAL METALLURG, P52
[8]   THE APPLICATION OF CONVERGENT-BEAM ELECTRON-DIFFRACTION TO THE DETECTION OF SMALL SYMMETRY CHANGES ACCOMPANYING PHASE-TRANSFORMATIONS .1. GENERAL AND METHODS [J].
ECOB, RC ;
SHAW, MP ;
PORTER, AJ ;
RALPH, B .
PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES, 1981, 44 (05) :1117-1133
[9]   THE MEASUREMENT OF PRECIPITATE MATRIX LATTICE MISMATCH IN NICKEL-BASE SUPER-ALLOYS [J].
ECOB, RC ;
RICKS, RA ;
PORTER, AJ .
SCRIPTA METALLURGICA, 1982, 16 (09) :1085-1090
[10]   CORRELATION OF MICROSTRUCTURE AND CREEP STAGES IN THE (100) ORIENTED SUPERALLOY SRR-99 AT 1253-K [J].
FELLERKNIEPMEIER, M ;
LINK, T .
METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 1989, 20 (07) :1233-1238
123456