1.
Ingo Hahn, Jörg C. Sturm
MAGMA GmbH, Aachen, Germany
SIMULATION EVOLVES TO AUTONOMOUS OPTIMIZATION

2.
Moritz Riebisch, Björn Pustal, Andreas Bührig-Polaczek
Gießerei-Institut der RWTH Aachen, Germany
ACCUMULATIVE IMPACT OF ALLOYING ELEMENTS ON THE MICROSTRUCTURE OF SOLID SOLUTION STRENGTHENED DUCTILE IRON

3.
Rebeka Rudolf1,2, Mohammed Shariq1,3, Urban Ferčec4, Alojz Križman1, Peter Majerič1,2
1 University of Maribor, Faculty of Mechanical Engineering, Smetanova 17, 2000 Maribor, Slovenia
2 Zlatarna Celje d.o.o., Kersnikova 19, 3000 Celje, Slovenia
3 Indian Institute of Technology (ISM), Dhanbad, Jharkhand 826 004, India
4 University of Ljubljana, Faculty of Chemistry and Chemical Technology, 1000 Ljubljana, Slovenia
NANOTECHNOLOGY IN METALLURGY: STATUS ANALYSIS AND PREDICTION OF DEVELOPMENT

4.
Betik C. Wilding
Omega Foundry Machinery Ltd, Peterborough, United Kingdom
SECONDARY NO-BAKE SAND RECLAMATION TECHNOLOGY TO REDUCE THE COST AND IMPROVE THE FOUNDRY ENVIRONMENT

1.
Ingo Hahn, Jörg C. Sturm
MAGMA GmbH, Aachen, Germany
SIMULATION EVOLVES TO AUTONOMOUS OPTIMIZATION

Abstract

Several examples have been used to show how the complete integration of autonomous optimization in the casting process simulation tool MAGMA5 can be used to ensure optimized and robust casting layouts and process windows before the first metal is poured. The software searches for the best possible process parameters, optimal runner and gate positions and dimensions, as well as locations and sizes of risers and chills. Foundry engineers can use autonomous optimization as a virtual field for experimentation, to simultaneously achieve different quality and cost targets.

The goal to retain the user-friendliness of the simulation tool, while integrating this new methodology, was achieved through the implementation of capabilities for parametric geometry creation and automatic parameter variation, together with tools for statistical analysis of autonomous designs of experiments and genetic algorithms for autonomous optimization. The simultaneous assessment of the derived results enables the foundry engineer to easily compare and evaluate outcomes from numerous simulations. Dependencies between design and process variables, quality criteria and objectives are clearly visualized.

Thirty years after the introduction of casting process simulation, foundry engineers now can combine single simulations, autonomous DOEs and autonomous optimizations to gain better process understanding and to establish robust casting processes making quality castings at the lowest possible cost.

Abstract

Steel scrap is one of the most important feedstocks for manufacturing ductile iron (DI) for reasons of cost savings. The amount of tramp elements in steel scraps is on the increase. In the work presented we focus on pearlite and carbide promoting elements such as chromium, copper, manganese, molybdenum, niobium or vanadium which can have a negative impact on the microstructure and the mechanical properties of DI, especially ferritic grades. Thus, the costs for producing ferritic grades with clean steel scrap will increase. Innovative solid solution strengthened ductile iron grades (SSDI) have a larger solubility for carbide promoting elements which enables the use of mixed scraps to some extent. However, the limiting concentrations of these elements are unknown. In the study presented, the individual and combined effect of pearlite and carbide promoting elements in the SSDI grade EN-GJS- 500-14 are investigated by means of a factorial design of experiment. Quantitative relations between chemical composition and microstructure were modelled by regression calculations. The results establish a basis for the reliable production of SSDI taking into account future scrap compositions with increasing amounts of tramp elements.

Progress in metallurgy in the second half of the twentieth century is connected with the rapid replacement of basic production systems, and we can say that this is a period of a new technical revolution. Within these frameworks there are known modifications of electro-melting systems, introduction of new processes of heat treatment of steels and vacuum refining, continuous casting, as well as powder metallurgy and hydro-extrusion. All this represents new approaches for the production of high-quality steels. In the last decade, progress has been made in metallurgy, primarily through the development of nanotechnology, especially in the field of manufacturing high quality materials for use in Electronics, Optics, Construction, Energy, Manufacturing, Astronautics and elsewhere. Some of the principles of nanotechnology are already being used in the "metallurgy in bulk" procedures for achieving large plastic deformation in the appropriate tool (in closed matrices and closed rolling grooves) or in thermo-reduction with a high degree of reduction or in a low temperature final deformation. In contrast, nanotechnology is less important in metallurgy of ferrous metals. At present, the serial production of quality rolled steel still relies on alloying. The cost of producing such finely grained steels without oxides and other non-metal inclusions is high. Steel, which has a fine grain microstructure, is significantly better, because it represents an indirect guarantee for high strength, stability at low/high temperatures and resistance to corrosion. The competitiveness of metallurgical products on the world market depends primarily on these properties of steels, since it allows them to be used for a wide variety of applications. Taking into account that during use, these steels are subjected to varying stresses and are subjected to high plastic deformations, the presence of defects and various inclusions in the microstructure is undesirable, as this can lead to a breakdown of material or construction before its time. Therefore, it is necessary to know the possible scenarios of the life of such products. Simulation based on nanostructuring has recently been used for life-cycle calculations. In the simulations, the strengths of individual nanophases are calculated in the maximum tension zones with a selected matrix phase fragmentation. Calculations show that the strength and lifetime of such a product depends on its initial structure and dynamic-structural changes, as well as from the self- organisation of the hardening of nanocomposite phases that disperse the energy input. An ordered nanocomposite has significantly better properties hardness, strength and plasticity, compared to the unordered. By regulating the formation of a fine-grained structure, we allow the formation of an ordered nanocomposite which is not only solid, but also plastic and cold transformable. This is the basis for the simplification of the thermo-mechanical treatment of such steels.

We can conclude that the process of manufacturing of various steels is related to achieving a fine grain structure with a maximum content of hardening metal nanoparticles (carbides, nitrides, carbo nitrides, intermetallic phases) and with minimum sulphur, phosphorus, oxide and other non- metallic inclusions. Today, this nanosystemic approach to the treatment of steels seems to be very promising.

Key words: metallurgy, nanotechnology, hardening, simulations

4.
Betik C. Wilding
Omega Foundry Machinery Ltd, Peterborough, United Kingdom
SECONDARY NO-BAKE SAND RECLAMATION TECHNOLOGY TO REDUCE THE COST AND IMPROVE THE FOUNDRY ENVIRONMENT

Abstract

A Middle Eastern steel foundry was informed by the local environmental agencies that due to the area in which they were located, they would have to close if a reduction in the level of casting fumes was not found.

The foundry in question is a chemically bonded sand foundry using the Alkaline Phenolic process for mould and core productions. They produce mainly manganese steel, stainless steel and other wear resistant steel castings from 3 kg up to 10 tons by using a combination of a mechanised moulding line, floor moulding and primary mechanical reclamation.

They have approached binder manufacturers, who have already been working on a high strength/low addition Alkaline Phenolic resin with less fume. They have also approached equipment suppliers to find a solution for their fume issue.

After a lengthy search, the found of a specific type of secondary mechanical reclamation (USR System) (fig 1) was the solution. This lecture is about the trial results and findings of the secondary mechanical reclamation equipment and the positive effect of secondary mechanical reclamation on fume reduction as well as other improvements of the cost efficiency and casting quality.

Key words: Fume reduction, mechanical secondary reclamation, USR, sand reclamation for Alkaline Phenolic process.