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ABSTRACTIn 1923 Poland introduced an extraordinary wealth tax. I have used internal statistics of the Ministry of the Treasury to estimate wealth inequality in interwar Poland. This data source was not previously used by researchers. There are no estimates of wealth inequality in interwar Poland available in the literature. According to my estimates, the top 0.01% of wealth owners controlled 14.8% of total private wealth. The wealth share of the top 1% stood at 37.5%. The top decile owned 60.7% of total private wealth. Wealth inequality varied strongly by region. A comparison of wealth inequality in Poland with wealth inequality in other European countries in the interwar period yields a diverse picture. The wealth share of the top 0.01% was the highest in Europe, the wealth share of the top 1% was in the middle of the European ranking, and the wealth share of the top 10% was almost the lowest in Europe. The small elite of super-rich (0.01%) controlled a higher share of national wealth than their European peers, but the wealth share of the rest of the top decile was relatively low. The unequal development of former partitions may partially explain the very high top wealth shares.

In this work, the evolutions of stresses in both phases of the Al/SiC p composite subjected to thermal cycling during in situ compression test were measured using Time of Flight neutron diffraction. It was confirmed that inter-phase stresses in the studied composite can be caused by differences in the coefficient of thermal expansion for the reinforcement and matrix, leading to a different variation of phase volumes during sample heating or cooling. The results of the diffraction experiment during thermal cycling were well predicted by the Thermo-Mechanical Self-Consistent model. The experimental study of elastic-plastic deformation was carried out in situ on a unique diffractometer EPSILON-MDS (JINR in Dubna, Russia) with nine detector banks measuring interplanar spacings simultaneously in 9 orientations of scattering vector. For the first time, the performed analysis of experimental data allowed to study the evolution of full stress tensor in both phases of the composite and to consider the decomposition of this tensor into deviatoric and hydrostatic components. It was found that the novel Developed Thermo-Mechanical Self-Consistent model correctly predicted stress evolution during compressive loading, taking into account the relaxation of thermal origin hydrostatic stresses. The comparison of this model with experimental data at the macroscopic level and the level of phases showed that strengthening of the Al/SiC p composite is caused by stress transfer from the plastically deformed Al2124 matrix to the elastic SiC p reinforcement, while thermal stresses relaxation does not significantly affect the overall composite properties. [ABSTRACT FROM AUTHOR]

The growth of total factor productivity (TFP) in advanced economies has slowed significantly after the 1970s. The global financial crisis (GFC) has resulted in the second productivity growth slowdown. This paper, on the basis of a broad literature review, identifies the structural forces and legacies of the financial crisis, explaining the productivity growth slowdown and providing possible policy solutions. The mismeasurement hypothesis is also discussed. The slowing pace of innovations, population aging, slowing human capital accumulation, limits of structural transformation, capital misallocation, and firm-level factors are identified as structural forces slowing TFP growth. Lack of capital deepening, financial frictions, and slowdown of international trade are the most important legacies of GFC affecting productivity growth.

The ageing of society means that public pension systems are becoming increasingly important. This study evaluates the influence of public pension entitlements on wealth inequality among pensioners. A novel data source - the Eurosystem Household Finance and Consumption Survey – is used to compare the impact of the public pension system on wealth inequality in 19 European countries. Findings indicate that in all investigated countries, social security wealth reduces wealth inequality. Augmented wealth inequality is ca. 30% lower than private wealth inequality. This estimate refers to the population of pensioners, while in the whole population the equalizing impact of public pension systems may be weaker. Social security wealth mitigates not only wealth inequality measured at the country level, but also wealth inequality in the whole European Union.

The goal of this work was to study the asymmetric rolling process using the Finite Element Method (FEM) coupled with the deformation model of polycrystalline material. The Leffers-Wierzbanowski (LW) model was selected to be implemented into FEM. This implementation enables a study of heterogeneous plastic deformation process, like asymmetric rolling, taking into account its crystallographic nature. The asymmetric rolling was realized using two identical rolls, driven by independent motors, rotating with different angular velocities. This enabled to obtain a controlled range of rolling asymmetry. Our aim was to examine the properties of asymmetrically rolled commercially pure titanium (Grade 2).

Asymmetric rolling is a promising forming technique offering numerous possibilities of material properties modification and the improvement of technological process parameters. This geometry of deformation is relatively easy to implement on existing industrial rolling mills. Moreover, it can provide large volume of a material with modified properties. The study of microstructure, crystallographic texture and residual stress in asymmetrically rolled titanium (grade 2) is presented in this work. The above characteristics were examined using EBSD technique and X-ray diffraction. The rolling asymmetry was realized using two identical rolls, driven by independent motors, rotating with different angular velocities ω1 and ω2. This ensured a wide range of rolling asymmetry: A=ω1/ω2. It was found that a strong shear stress induced in the asymmetrically rolled material allowed to obtain a microstructure refinement, texture homogenization and lowering of residual stress.

Rotation of grain crystal lattice is the basic mechanism of texture formation and of anisotropic behavior of metals during plastic deformation. The classical definition of crystal lattice rotation leads in some cases to different texture and residual stress predictions than the definition based on the orientation preservation of selected sample planes and/or directions. Also the intensity of grain-matrix interaction plays an important role in the prediction of the above quantities. These problems were studied using elasto-plastic deformation model of polycrystalline materials. Examples of austenite and ferrite steels were considered.

The relation between residual stresses occurring in plastically deformed material and after subsequent annealing is of practical and theoretical importance. In the present work the X-ray multi-reflection method was applied to determine residual stresses and their orientation distribution in rolled and annealed ferrite and austenite steel samples. An important decrease of the first- and the second-order residual stresses was observed during recovery and recrystallization processes. Diffraction peak width was also studied and correlated with stress variation during annealing. Different kinetics of stress relaxation in ferrite and austenite were explained by different levels of stacking fault energy and different types of intergranular interactions occurring in these materials.

The classical definition of lattice rotation leads in some cases to different textures than the definition based on the preservation of orientations of selected sample directions and/or planes. For example, if classical {111} slip is taken into account for f.c.c. materials, the former approach enables to predict both copper and brass types of rolling texture, while classical approach predicts only the first one. The analysis of rolling texture formation is done for two types of lattice rotation in function of grain-matrix interaction parameter used in a deformation model. Predicted textures and correlation factors estimating the similarity of predicted and experimental textures are presented.

Formation of residual stresses and crystallographic textures during rolling have been studied using elasto-plastic deformation for polycrystalline material (Leffers-Wierzbanowski model). The rotation of grain crystal lattices is the basic mechanism of texture formation and anisotropic behavior of metals during plastic deformation. The classical definition of crystal lattice rotation leads in some cases to different texture predictions than the definition based on the orientation preservation of selected sample planes and/or directions (preservation condition). Also predicted residual stresses can be influenced by a choice of rotation definition. In the used deformation model of polycrystalline material, the intensity of grain-matrix interaction is described by the parameter L= aG, where G is shear modulus and a is elasto-plastic accommodation parameter. Model calculations have been done for different values of this parameter and for two definitions of lattice rotation. The predicted second order residual stresses and crystallographic textures for cold rolled ferrite steel are compared with experimental ones.