S. Węglarczyk

System for design of the manufacturing process of connecting parts for automotive industry

The proposition of complex hybrid system, dedicated to modelling of life cycle of materials and optimization of their in use properties, is presented in the paper. The approach is based on the conventional optimization algorithms, FE simulations of industrial production process and knowledge base, containing both theoretical and practical data in form of rules, facts and equations. Simulation and optimization of the manufacturing of the connecting part used in automotive industry was selected for the purposes of this work. The particular emphasis is put on control of selected in use properties of products by proper design of technological parameters for consecutive stages of the production chain. The concept of the life cycle modelling used in the proposed system, as well as results obtained from simulations, are also presented in the paper.

Computer Aided Design of Manufacturing of Fasteners - Selection of the Best Production Chain

Computer aided design of the manufacturing technology for the fasteners is presented the paper. The particular objectives of the work were twofold. The first objective is evaluation of applicability of various materials for fasteners. Analysis of different technological variants is the second objective of the research. In the material part, bainitic steels are considered as an alternative for the commonly used carbon-manganese steels. This is a continuation of [1,2]. Possibility of elimination of the heat treatment was evaluated. Main features of the new generation of bainitic steels are discussed briefly in the paper. Rheological models for all steels investigated in the project were developed. The models were implemented into the finite element code for simulations of drawing and multi stage forging. Simulations of various variants of manufacturing chain were performed and the best alternative was selected. Criteria for the selection composed dimensional accuracy and tool life. Industrial trials were performed for the selected cycle and the efficiency of this cycle was evaluated. Finally, the optimization task was formulated. However, solution of the optimization problem is costly at this stage and improvement of the efficiency of the formulation will be the objective of further research. References 1. Kuziak R., Skóra M., Węglarczyk S., Paćko M., Pietrzyk M., Computer aided design of the manufacturing chain for fasteners, Computer Methods in Materials Science, 11, 2011, 243-250. 2. Kuziak R., Pidvysots’kyy V., Węglarczyk S., Pietrzyk M., Bainitic steels as alternative for conventional carbon-manganese steels in manufacturing of fasteners - simulation of production chain, Computer Methods in Materials Science, 11, 2011, 443 – 462.

Computer-Aided Design of Manufacturing Chain Based on Closed Die Forging for Hardly Deformable Cu-Based Alloys

Two copper-based alloys were considered, Cu-1 pct Cr and Cu-0.7 pct Cr-1 pct Si-2 pct Ni. The thermal, electrical, and mechanical properties of these alloys are given in the paper and compared to pure copper and steel. The role of aging and precipitation kinetics in hardening of the alloys is discussed based upon the developed model. Results of plastometric tests performed at various temperatures and various strain rates are presented. The effect of the initial microstructure on the flow stress was investigated. Rheologic models for the alloys were developed. A finite element (FE) model based on the Norton–Hoff visco-plastic flow rule was applied to the simulation of forging of the alloys. Analysis of the die wear for various processes of hot and cold forging is presented as well. A microstructure evolution model was implemented into the FE code, and the microstructure and mechanical properties of final products were predicted. Various variants of the manufacturing cycles were considered. These include different preheating schedules, hot forging, cold forging, and aging. All variants were simulated using the FE method and loads, die filling, tool wear, and mechanical properties of products were predicted. Three variants giving the best combination of forging parameters were selected and industrial trials were performed. The best manufacturing technology for the copper-based alloys is proposed.

Computer Aided Design of Manufacturing of Anchors and Formulation of the Optimization Task for in Use Properties

Computer aided design of the manufacturing technology for anchors is presented in the paper. Evaluation of applicability of various materials for anchors, as well as analysis of the influence of process parameters on the in use properties of product, were the objectives of the research. In the material part, bainitic steels were considered as an alternative for the commonly used C-Mn steels. Possibility of elimination of the heat treatment was evaluated. Rheological models for the investigated steels were developed and implemented into the finite element code for simulations of drawing and multi stage forging. Criteria for the selection of the best manufacturing chain composed dimensional accuracy, tool life and product properties. Industrial trials were performed for the selected cycle and the efficiency of this cycle was evaluated. Finally, simulations of the in use behaviour of the anchor-concrete joint were performed. On the basis of the simulations the optimization task using strength of the joint as the objective function was formulated

Experimental Investigations And Numerical Modelling of 210CR12 Steel in Semi-Solid State

Experimental investigation, including hot compression and simple closed die filling was performed. Temperature range of tests was between 1225 °C and 1320 °C. Temperature selection was adequate with liquid fraction between 20 and 60%, which is typical for thixoforming processes. In the die filling test, steel dies with ceramic layer was used (highly refractory air‐setting mortar JM 3300 manufactured by Thermal Ceramics). Experiments were carried out on the Gleeble 3800 physical simulator with MCU unit. In the paper, methodology of experimental investigation is described. Dependency of forming forces on temperature and forming velocities is analysed. Obtained results are discussed. The second part of the paper concerns numerical modelling of semi‐solid forming. Numerical models for both sets of test were developed. Structural and Computational Fluid Dynamics models are compared. Initial works in microstructural modelling of 210CR12 steel behaviour are described. Lattice Boltzman Method model for thixotropi...