Jerzy Stobrawa

Ultrafine Grained Copper Alloys Processed by Continuous Repetitive Corrugation and Straightening Method

A growing trend to use new copper-based functional materials is observed recently world-wide. Within this group of materials particular attention is drawn to those with ultrafine grain size of a copper matrix. This study was aimed to investigate mechanical properties, electrical conductivity and microstructure in strips of precipitation strengthened copper alloys processed by continuous repetitive corrugation and straightening (CRCS). Tests were performed with the copper alloy strips using original die set construction installed on tensile testing machine. The microstructure was investigated using optical and electron microscopy (TEM and SEM equipped with EBSD). Proposition of semi industrial application of this method have been also presented. The CRCS process effectively reduced the grain size of a copper alloy strips, demonstrating the CRCS as a promising new method for producing ultra fine grained metallic strips.

Effect of Continuous RCS Deformation on Microstructure and Properties of Copper and Copper Alloys Strips

The aim of this work was to study the microstructure and mechanical properties of copper, brass CuZn36 and bronze CuSn6 strips annealed and after repetitive corrugation and straightening (RCS) process. The influence of process parameters on the functional properties of strips was investigated. The study found an increase in the yield strength and tensile strength of the material after RCS process. Crystallite size measurement confirmed the presence of nanoscale structures in the studied materials after deformation by RCS process. The used method of plastic deformation is promising for development materials with improved functional properties. The paper presents also the results of numerical simulations of Cu strip after corrugation on groove and tooth rolls and next straightening. Rolling process simulations were conducted using Forge 2011® based on the finite element method.