Papers by Author: Christian R. Simon

Abstract: Polymer materials are utilized in an increasing number of categories of products, such as components for cars, boats, airplanes, within the electronics industry and other advanced industry as well as in paints and other coatings, for special packaging etc. The uses of polymer materials in new categories of products are only limited by the product properties. It is thus a continuous need for developing polymer products with improved properties like increased scratch resistance, improved weather resistance, increased UV resistance, chemical resistance and antioxidation. In addition to pure polymer materials, new products based on hybrid organic inorganic materials involving macromolecules with inorganic core and organic branches have been developed. In this paper, organic inorganic hybrid polymers (HP) are prepared based on a new technology and applied as additives for polymer products like thermoset plastics and in lacquers and other types of coatings for surface protection. Used in appropriate amounts and with suitable particle size, such hybrid polymers contribute to a significant improvement of the properties of the plastic material or the lacquer, hereunder an increased wear resistance/scratch resistance and/or weather resistance. It is shown that HP additives are suitable for a number of applications within organic chemistry and in particular within polymer chemistry and can be used as a stabilizer for thermoplastics with a broader range of utility than known mono-functional stabilizers.

Abstract: The main objective of this work is to contribute to the study of the 301LN unstable austenitic stainless steel by determining the distribution of residual stresses after deep drawing, taking into account the phase transformation. In the first part, kinetics of martensitic transformation are determined for uniaxial loading. Tensile tests are performed at different pre-strains at room temperature for two different strain rates. The austenite/martensite content is measured by X-ray diffraction and is coupled with the determination of residual stresses distribution. In addition, to establish a relation between the complex loading path effect and the residual stresses state, deep drawing are done for different drawing ratios for two different temperatures. Macroscopic tangential residual stresses are determined by the separation technique. It appears that the residual stresses increase with increasing drawing ratios and the maximum value is located at middle height of the cup.