Microstructures and hardness of ultrafine-grained Ni[sub 3]Al

The microstructural evolution of the ultrafine-grained intermetallic compound Ni[sub 3]Al is studied as a function of annealing at different temperatures. The ultrafine microstructure is produced by a high plastic torsional straining. Transmission electron microscopy, X-ray diffraction and different...

Full description

Saved in:
Bibliographic Details
Published in:Acta metallurgica et materialia 1993-10, Vol.41:10
Main Authors: Languillaume, J., Chmelik, F., Kapelski, G., Bordeaux, F., Nazarov, A.A., Canova, G., Valiev, R.Z., Baudelet, B., Esling, C.
Format: Article
Language:English
Subjects:
360102 - Metals & Alloys- Structure & Phase Studies
360103 - Metals & Alloys- Mechanical Properties
ALLOY SYSTEMS
ALLOYS
ALUMINIUM ALLOYS
BINARY ALLOY SYSTEMS
CALORIMETRY
COHERENT SCATTERING
DEFORMATION
DIFFRACTION
ELECTRON MICROSCOPY
HARDNESS
INTERMETALLIC COMPOUNDS
MATERIALS SCIENCE
MECHANICAL PROPERTIES
MICROSCOPY
MICROSTRUCTURE
NICKEL ALLOYS
NICKEL BASE ALLOYS
RECRYSTALLIZATION
SCATTERING
STRAINS
TEXTURE
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The microstructural evolution of the ultrafine-grained intermetallic compound Ni[sub 3]Al is studied as a function of annealing at different temperatures. The ultrafine microstructure is produced by a high plastic torsional straining. Transmission electron microscopy, X-ray diffraction and differential scanning calorimetry are used to characterize the microstructural evolution and microhardness is used to determine mechanical behavior. The as-deformed microstructure exhibits an almost fully disordered crystalline structure with coherent domain size of about 18 nm, a strong torsional texture and high internal elastic strains. On annealing the as-deformed samples at different temperatures, the recrystallization of the material into a granular type structure containing non-equilibrium grain boundaries is first observed. This is followed by the transformation from non-equilibrium into equilibrium grain boundaries with simultaneous grain growth. This transformation is correlated with an increase of hardness. A new concept of non-equilibrium grain boundaries transparency is presented to interpret this singular behavior. The results are compared to those obtained on an ultrafine-grained Al-1.5% Mg alloy produced by the same technique and which exhibits the same mechanical behavior.
ISSN:0956-7151
1873-2879
DOI:10.1016/0956-7151(93)90110-E