DRUŠTVO LIVARJEV SLOVENIJESLOVENIAN FOUNDRYMEN SOCIETY
Član The World Foundry OrganizationMember of World Foundry Organization

1.

H.Polzin, T. Kooyers:

EXPERIENCES WITH THERMOSETTING INORGANIC MOLDING BINDER SYSTEM

Abstract

We report on a hot-air curing inorganic core-making process already presented at previous events, which works without an actively heated core-making tool. [1] A number of positive experiences have been made with this system recently. The properties of molding compounds produced with the binder system are presented, for example, the achievable strengths under different solidification conditions or the residual tension after pouring of the castings. Although the system was developed in particular for customer foundries operating in the iron or steel casting sector, core examples from both the iron and non-ferrous casting sectors are shown. Although the binder system was originally developed for curing the molding material with hot air at about 160°C, the system can also be used without further ado with any heated steel core boxes that may be present.

The presented inorganic binder system based on water glass represents an alternative to the PUR cold box process that can be used in iron and steel casting. The liquid one-component binder is metered at a lower rate than comparable binder systems; binder quantities used to date are between 1.5 and 2.5 %, but can also be increased if required. The single-component system facilitates binder metering on the core shooter, and the desired strengths are ensured via comparably higher specific strengths. The curing of the manufactured cores takes place via 160°C warm gassing air. The core making tool is not heated in the process. When selecting the core box material, care should be taken to use appropriately thermally resistant plastics. Core boxes made of metal (aluminum or steel) offer advantages in terms of shorter cycle times. When using particularly dry air, curing can be realized at lower temperatures. The binder system can, of course, also be used in the warm or hot box process. The fact that sheet veining only occurs in exceptional cases with the inorganically bonded cores is certainly a welcome advantage in the blowroom. The residual tension or decoring behavior is very similar to that of the PUR cold box process. In addition to the binders designed for iron and steel castings, variants for aluminum or copper castings are also available.

2.

M. Manapuram:

RECASTING THE CASTING OPERATIONS VIS- A- VIS CASTING INPUT- OUTPUT SUPPLY CHAIN MANAGEMENT

Abstract

World population has reached 8.0 billion as of June 2022 as per estimates of worldometer. India is the second largest casting manufacturer (11.31 million tons in 4500 foundries) in the world as per world casting census 2021. Globally annual casting production of 105.5 million tons in more than 46,500 foundries in 34 nations 2021 AD. Foundries are broadly classified as captive foundry (integral part of an organization and it makes castings for the same), jobbing foundry (makes small number of castings for different customers), production foundry (produces castings on mass scale economically) and semi-production foundry (combination of production and jobbing foundry) based on their nature of work. Foundry needs large quantities of input raw material and produces output castings for different user industries like automobile, machine tools, railways, aircraft, marine industry on land, seas and air. Casting input-output model and supply chain management are vital for casing industry. New technologies pose fresh problems to the existing casters like electric vehicles, additive manufacturing etc. Metal casters as well as foundry owners need to recasting their casting operations suitable to the changing scenario. Hence in the present

work an attempt has been made to recast the casting operations suitable for changing technologies and supply chain management systems required for inputs raw materials required and output castings produced.

Key words:  casting, supply chain management, world casting census, worldometer, 3-dimensional print

3.

I.Jandrlić, F. Kozina, T. Brlić, L. Mrkobrada:

CHANGES IN STRUCTURE AND PROPERTIES OF COPPER WIRE DURING THE PRODUCTION AND PROCESSING

Abstract

Irreplaceability of copper, as an electrical conductor, makes it the most important non-ferrous metal in application. The most frequently used methods of producing the copper conductors involves continuous casting of the copper wire, subsequent cold drawing deformation and heat treatment processes to improve copper mechanical and electrical properties. In this paper the research was performed on copper wire produced by continuous casting. During production various structural changes and changes in mechanical properties occur. To investigate those changes and to clarify their influence on final product, structure and hardness were recorded and measured in all stages of production. While macrostructure and microstructure were observed by light microscopy, the hardness was measured using Vickers hardness testing method. The results indicate that the initial coarse-grained structure in as-cast condition, brakes down into a fine-grained structure during reduction. Those fine grains are orientated in the direction of cold drawing during plastic deformation. There is an increase in the hardness. The purpose of heat treatment is to achieve better conductivity while maintaining good mechanical properties. The results of microstructure analysis indicate the presence of twin crystals in the structure of the final product.

4.

M.Mencej:

TIME EFFICIENT TECHNICAL CLEANLINESS ANALYSIS WITH A MICROSCOPE

Summary

Technical Cleanliness Analysis is becoming more and more important in the industrial production. The producers of the components as well as the buyers of components are demanding detailed analysis of impurities on the surface of products. The basic standards for technical cleanliness analysis are VDA 19.1 and ISO 16232. For the area of medical equipment and oil analysis other standards are available.

The basic analysis can be performed with a light microscope. This enables the classification by size and shape, and differentiation between reflecting and non-reflecting particles. For a more detailed analysis of the chemical composition of the impurities we need an electron microscope.

ZEISS offers solutions in both light and electron microscopy. We also offer solutions in the field of correlative microscopy, which links the light microscopes with the electron microscopes.

Key words:  technical cleanliness analysis, light microscopy, raster electron microscopy, built in polarisation, standards VDA 19.1 and ISO 16232.