本书讨论了多晶体材料中超塑性和晶界滑动的问题,探讨了晶界形成和演化的微观结构,分析了经过剧烈塑性变形的材料的晶界、纹理和系综的变化,同时考察了晶界在晶粒间界扩散、弛豫和晶粒生长过程中的作用。
本书适合从事超塑性研究的相关人员使用,也可供高等院校相关专业的师生参考。
【目 录】
1
STRUCTURAL SUPERPLASTICITY OF POLYCRYSTALLINE MATERIALS
1.1.Structural levels,spatial scales and description levels
1.2 Structural superplasticity:from the combination of mechanisms to cooperative grain boundaries sliding
1.3.Structural superplasticity:from meso—description to macrochafacteristics
References
2
CHARACTERISTICS OF GRAIN BOUNDARY ENESEMBLES
2.1.Crystal geometry and structure of intercrystalline boundaries
2.2.Special grain boundaries in the monoclinic lattice
2.3.Description of the grain boundary misorientation distribution(GBMD)
2.4.Computer model of a polycrystal:a calculation algorithm
References
3
ORIENTATION—DISTRIBUTED PARAMETERS OF
THE POLYCRYSTALLINE STRUCTURE
3.1.The distribution function of the grains with respect to crystallographic orientations:calculation methods
3.2.Relationship between the grain boundary misorientation distribution and the ODF
3.3.Correlation orientation of adjacent grains:the concept of the basis spectra of misorientation of the grain boundaries
3.4.Modelling the misorientation spectra of the grain boundaries in the FCC crystals with modelling ODF
4
EXPERIMENTAL INVESTIGATIONS OF GRAIN BOUNDARY
ENSEMBLES IN POLYCRYSTALS
4.1.Diffraction methods of measuring misorientation
4.2 Experimental spectra of the grain boundaries in FCC polycrystals
4.3.Orientation distribution function in Ni—Cr alloy:experimental and modelling GBMDs
4.4.Special features of the grain boundaries in the FCC materials with a high stacking fault energy
References
5
GRAIN BOUNDARY SLIDING IN METALLIC BI—AND TRICRYSTALS
5.1.Dislocation nature of grain boundary sliding (GBS)
5.2.Formulation of the model of stimulated grain boundary sliding
5.3.Formal solution and its analysis
5.4.Special features of pure grain boundary sliding
5.5.Local migration of the grain boundary as the mechanism of reorganisation of the triple junction: weak migration
approximation
5.6.Variance formulation of the system of equations for the shape of the boundary and pile—up density
5.7.The power of pile—ups of grain boundary dislocations
References
6
PERCOLATION MECHANISM OF DEFORMATION PROCESSES IN
ULTRAFINE—GRAINED POLVCRVSTALS
6.1.Pcrcolation mechanism of the formation of a band of cooperative grain boundary sliding
6.2.Conditions of formation of CGBS bands as the condition of realisation of the superplastic deformation regime
6.3.Shear rate along the CGBS band
6.4.Kinetics of deformation in CGBS bands
6.5.Comparison of the calculated values with the expcrimental
results
Refercnces
7
PERCOLATION PROCESSES IN A NETWORK OF GRAIN
BOUNDARIES IN ULTRAFINE—GRAINED MATERIALS
7.1.Effect of grain boundaries on oxidation and diffusion processes in polycrystalline oxide films
7.2.High—resolution electron microscopy of zirconium oxide:grain clusters,surrounded only by special boundaries
7.3.Effect of the statistics of the grain boundaries on diffusion in zirconium oxide
7.4.Special Features of oxidation kinetics under the effect of stresses at the metal/oxide boundary
7.5.Texture and spectrum of misorientation of the grain boundaries in an NiO film on(100)and (111)substrates:modelling and experiments
References
8
MICROSTRUCTURE AND GRAIN BOUNDARY ENSEMBLES IN
ULTRAFINE—GRAINED MATERIALS
8.1.Methods of producing ultrafine—grained and nanostructured materials by severe plastic deformation
8.2 Effect of the parameters of quasi—hydrostatic pressure on the microstructure and grain boundary ensembles in nickel
8.3.Spectrum of misorientation of grain boundaries in ultrafine—grained nickel
8.4.Advanced methods of automatic mcasurement of the grain boundary parameters
8.5.The misorientation distribution of the grain boundaries in ultrafine—grained nickel:experiments and modelling
References
9
GRAIN BOUNDARY PROCESSES IN ULTRAFINE—GRAINED NICKEL
AND NANONICKEL
9.1.Grain growth kinetics in ECAP specimens
9.2.Activation energy and stored enthalpy in ultrafine—grained nickel
9.3.Evolution of the microstructure and texture in HPT nickel in annealing
9.4.Superplasticity of nanocrystalline nickel
References
10
DURATION OF THE STABLE FLOW STAGE IN SUPERPLASTIC
DEFORMATION
10.1.Superplastic capacity and the rate sensitivity parameter
10.2.Description of thickness differences of a flat specimen in tensile deformation
10.3.Formation of thickness difference as a random process
10.4.Absorption condition and the equation for limiting strain
10.5.Some properties of limiting strain
References
11
DERIVATION OF CONSTITUTIVE EQUATIONS IN MULTICOMPONENT
LOADING CONDITIONS
11.1.From the deformation mechanism to constitutive equations
11.2.Kinematics ofpolycrystalline continuum
11.3.Strain rate tensor determined by shear along the CGBS bands
11.4.Degenerate cases and variants of coaxiality of the tensors
References
CONCLUSION
INDEX