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The essence of ablation casting technology consists in pouring castings into single-use moulds made from the mixture of sand and a water-soluble binder. After pouring the mould with liquid metal yet while the casting is still solidifying, the mould destruction (washing out, erosion) takes place using a stream of cooling medium, which in this case is water. This paper focuses on the selection of moulding sands with hydrated sodium silicate for moulds used in ablation casting. The research is based on the use of water glass 145 and 150 as binders. As part of the research, loose moulding mixtures based on two silica sands from different sand mines with different content of binders were prepared. The review of literature data and the results of own studies have shown that moulding sand with hydrated sodium silicate hardened by dehydration is characterized by sufficient strength properties to be used in the ablation casting process. Our own research also confirmed the possibility of using these sand mixtures in terms of both casting surface quality and sand reclamation. The results presented in this paper prove that both sand grains and types of binder tested may be used as components in moulding sands devoted to ablation casting.

In recent years, the demand for products made of biodegradable or partially biodegradable materials has been increasing. This is mainly due to the ever-increasing amount of waste in landfills, but also to the problem of post-production waste management. This problem also concerns waste from the casting process of sands made on the basis of furfuryl resin, as well as residues from the regeneration process of these sands. The article presents the issues related to the methodology of research on the biodegradation process both in the natural environment and methods conducted in laboratory conditions. The preliminary results of the research on the biodegradation process in the aquatic environment, to which the dusts from mechanical regeneration of moulding sand were subjected, indicate the directions of further research and work in the field of selection of components of moulding sand with biodegradable properties. These tests should be carried out primarily in terms of determining the minimum and maximum amount of the addition of a biodegradable component to the moulding sand.

The aim of the present work is to compare the properties of self-hardening moulding sands based on inorganic binders based on sodium silicate of different modules, geopolymer binders and phosphate binders and to prove they can be used in the ablation casting process. Ablation casting is a process in which, directly after pouring the liquid alloy, the mould is sprayed with water until it is completely eroded and a finished, cooled casting is obtained. The use of proecological water-dilutable binder makes it possible to recover the sand matrix after drying the suspension that remains after the process. Moulding sands were prepared on the basis of four inorganic binders available on the market. For each of the moulding sands the bending strength was tested after 1, 2, 4 and 24 h of hardening. Then, the masses with optimum bending strength were selected and subjected to gas emissivity tests. A thermal analysis of moulding sands selected for testing was also carried out in order to determine the loss of mass during annealing. The susceptibility of moulds to erosion under the influence of ablative medium was also assessed by measuring the time of mould erosion. Tests showed the possibility of using self-hardening moulding sands based on inorganic binders for the ablation casting process of aluminium-silicon alloys.

In the foundry industry, as in many other fields we seek to achieve the best quality with the least losses and the lowest cost. To meet these demands numerous plants increased automatization of their manufacturing processes. However, with changes in the production process it is necessary to change also the materials used. Not only casting alloys that are used in production, but also applied moulding and core sands are important. Proper selection and evaluation of the properties of used moulding mixtures is crucial in order to achieve a highly efficient production. In this article a new issue concerning the use of flexibility in foundry molding and core was mentioned. It explains the principles of measurement and interpretation of the obtained results for the cold-box moulding sands.

This article describes the impact of the metal mould temperature change in eliminating the adverse effect of iron in the AlSi7Mg0.3 alloy. The kind of phases based on iron to be formed in aluminium alloys is determined by the alloy chemical composition, the melt overheating temperature prior to casting, and the cooling rate during crystallisation. In the experiment, we used three various mould temperatures, and their impact on the possible change in the adverse Al5FeSi phase, excreted in a needle form to a more compact form of Chinese writing or skeleton units. The experimental part did not use melt overheat that would result in impairment of the melt, for example due to increased gassing of the melt, as well as in a greater load on the smelting unit, thus resulting in increased energy expenditure. We can conclude from the obtained results that the mould temperature change does not have an adequate effect in eliminating the adverse effect of iron in Al-Si-Mg alloys.

The aim of the article is thermal and structural analysis of new two-component binders for foundry moulding sands. The previous research showed the possibility of using biodegradable materials as binders or parts of binders’ compositions for foundry moulding and core sands. This paper is concentrated on estimating the influence of PCL on phenol-furfuryl resin thermal destruction (measured by derivatographic research) and its structure (measured by FTiR technology). The research proved that addition of new biodegradable additive PCL in the amount of 5-15% to the phenol-furfuryl resin doesn’t change the resin thermal destruction course but it results in appearance of a new band in two-component binder structure. What’s more there has been noticed a growth of intensity for band at wavenumber 1730 cm-1 (C = O) with the increasing addition of PCL.

This paper focuses on mechanical properties of self hardening moulding sands with furfuryl and alkyd binders. Elasticity as a new parameter of moulding sands is investigated. With the use of presented testing equipment, it is possible to determine force kinetics and deformation of moulding sand in real time. The need for this kind of study comes from the modern casting industry. New foundries can be characterized with high intensity of production which is correlated with high level of mechanization and automatization of foundry processes. The increasingly common use of manipulators in production of moulds and cores can lead to generation of new types of flaws, caused by breakage in moulds and cores which could occur during mould assembly. Hence it is required that moulds and cores have high resistance to those kinds of factors, attributing it with the phenomenon of elasticity. The article describes the theoretical basis of this property, presents methods of measuring and continues earlier research.

Growing emission requirements are forcing the foundry industry to seek new, more environmentally friendly solutions. One of the solutions may be the technologies of preparing moulding and core sands using organic biodegradable materials as binders. However, not only environmental requirements grow but also those related to the technological properties of moulding sand. Advancing automation and mechanization of the foundry industry brings new challenges related to the moulding sands. Low elasticity may cause defects during assembly of cores or moulds by the manipulators. The paper presents the study of flexibility in the room temperature according to new method and resistance to thermal deformation of self-hardening moulding sands with furfuryl resin, containing biodegradable material PCL. The task of the new additive is to reduce the moulding sands harmfulness to the environment and increase its flexibility in the room temperature. The impact of the additive and the effect of the amount of binder on the properties of mentioned moulding sands were analysed. Studies have shown that the use of 5% of PCL does not change the nature of the thermal deformation curve, improves the bending strength of tested moulding mixtures and increases their flexibility at room temperature.

The article shows the influence of environment requirements on changes in different foundry moulding sands technologies such as cold box, self-hardening moulding sands and green sands. The aim of the article is to show the possibility of using the biodegradable materials as binders (or parts of binders’ compositions) for foundry moulding and core sands. The authors concentrated on the possibility of preparing new binders consisting of typical synthetic resins - commonly used in foundry practice - and biodegradable materials. According to own research it is presumed that using biodegradable materials as a part of new binders’ compositions may cause not only lower toxicity and better ability to reclaim, but may also accelerate the biodegradation rate of used binders. What’s more, using some kinds of biodegradable materials may improve flexibility of moulding sands with polymeric binder. The conducted research was introductory and took into account bending strength and thermal properties of furan moulding sands with biodegradable material (PCL). The research proved that new biodegradable additive did not decrease the tested properties.

Modern techniques of castings production, including moulding sands production, require a strict technological regime and high quality materials. In the case of self-hardening moulding sands with synthetic binders those requirements apply mainly to sand, which adds to more than 98% of the whole moulding sand mixture. The factors that affect the quality of the moulding sands are both chemical (SiO2, Fe2O3 and carbonates content) and physical. Among these factors somewhat less attention is paid to the granulometric composition of the sands. As a part of this study, the effect of sand quality on bending strength Rgu and thermal deformation of self-hardening moulding sands with furfural and alkyd resin was assessed. Moulding sands with furfural resin are known [1] to be the most susceptible to the sand quality. A negative effect on its properties has, among others, high content of clay binder and so-called subgrains (fraction smaller than 0,1mm), which can lead to neutralization of acidic hardeners (in the case of moulding sands with furfuryl resin) and also increase the specific surface, what forces greater amount of binding agents. The research used 5 different quartz sands originating from different sources and characterized with different grain composition and different clay binder content.

The paper presents possibility of using biodegradable materials as parts of moulding sands’ binders based on commonly used in foundry practice resins. The authors focus on thermal destruction of binding materials and thermal deformation of moulding sands with tested materials. All the research is conducted for the biodegradable material and two typical resins separately. The point of the article is to show if tested materials are compatible from thermal destruction and thermal deformation points of view. It was proved that tested materials characterized with similar thermal destruction but thermal deformation of moulding sands with those binders was different.

The article discusses the issue of the influence of furfuryl alcohol content in resin binders on properties of moulding sand at elevated temperature. Reducing the share of this component - due to the requirements of the European Union regarding its toxicity - may cause a decrease in temperature of moulding sands’ destruction and, consequently, the thermal deformation of moulds and the creation of many casting defects. The study examined the impact of the furfuryl alcohol content of the thermal destruction processes and on the strength of the moulding sand at an ambient temperature and the tendency to thermal deformation.

Bentonite binders rank among the most widespread applied systems for the production of molds. Their resistance to high temperatures (thermal stability) is mainly defined by genesis of binders, chemical composition and the content of Montmorillonite. The aim of this contribution is to compare selected bentonite binders commonly used in the foundries of the Central European region, in different ways of the thermostability determination as a result of changes of the mechanical strengths of the bentonite bonded sand mixture. Masy formierskie z bentonitem jako materiałem wiążącym stanowią najbardziej rozpowszechnioną technologię otrzymywania form odlewniczych. Ich odporność na wysokie temperatury (stabilność termiczna) jest uzależniona od pochodzenia minerologicznego, składu chemicznego oraz zawartości montmorylonitu w bentonicie. Celem tego artykułu jest porównanie stabilności termicznej wybranych bentonitów - powszechnie stosowanych w odlewniach w regionie Europy Środkowej – mierzonej różnymi metodami. Kryterium oceny tych metod jest zmiana wytrzymałości mechanicznej mas formierskich wiązanych bentonitem. Web of Science 59 3 1044 1041

Artificial neural networks are one of the modern methods of the production optimisation. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. This paper presents the next part of the study on usefulness of artificial neural networks to support rebonding of green moulding sand, using chosen properties of moulding sands, which can be determined fast. The effect of changes in the training set quantity on the quality of the network is presented in this article. It has been shown that a small change in the data set would change the quality of the network, and may also make it necessary to change the type of network in order to obtain good results.

This article is devoted to ecological moulding sands with hydrated sodium silicate as binder. The inorganic nature of the binder results in poor knock-out properties and low ability to mechanical reclamation of tested moulding sands. In the present study authors focused on developing a new addition to the composition of these environmental friendly foundry moulding sands, providing them better knock-out properties. The analysis of the literature data let authors focus on the use of additives containing Al2O3 as components of moulding sands with hydrated sodium silicate. These additives provide better knock-out properties of moulding sands measured according to retained strength Rctk and also lead to lower thermal expansion of moulding sands. The authors have developed a new supplement containing Al2O3 and demonstrated its positive impact on moulding sand with hydrated sodium silicate knock-out properties.

Artificial neural networks are one of the modern methods of the production optimisation. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. The presented investigations were aimed at the selection of the neural network able to predict the active bentonite content in the moulding sand on the basis of this sand properties such as: permeability, compactibility and the compressive strength. Then, the data of selected parameters of new moulding sand were set to selected artificial neural network models. This was made to test the universality of the model in relation to other moulding sands. An application of the Statistica program allowed to select automatically the type of network proper for the representation of dependencies occurring in between the proposed moulding sand parameters. The most advantageous conditions were obtained for the uni-directional multi-layer perception (MLP) network. Knowledge of the neural network sensitivity to individual moulding sand parameters, allowed to eliminate not essential ones.

This paper presents a new perspective on the issue of reclamation of moulding and core sands. Taking as a premise that the reclamation process must remain on the surface of grains some not separated binding materials rests, it should be chosen the proper moulding sand’s composition that will be least harmful for the reclaim quality. There are two different moulding and core sands taken into examinations. The researches prove that a small correction of their compositions (hardener type) improves the quality of the received reclaims. Carried out in this article studies have shown that such an approach to the problem of reclamation of the moulding and core sands is needed and reasonable.

The article takes into consideration the researches concerning inserting the Glassex additive to the microwaved-hardened and self- hardened moulding sands with water glass. In the research different types of ester hardeners to self-hardened moulding sands with water glass were used. The influence of Glassex additive on retained strength of moulding sands with different hardeners and prepared by different technologies of hardening were tested. The influence of different hardeners and the technology of hardening on retained strength of moulding sand with water glass and the Glassex additive were also estimated.

One of the modern methods of the production optimisation are artificial neural networks. Neural networks are gaining broader and broader application in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castings and supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressure castings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. The presented investigations were obtained by using the Statistica 9.0 program. The aim of the investigations was to select the neural network suitable for prediction the moulding sand matrix grain size on the basis of the determined sand properties such as: permeability, compactibility, and compressive strength.

Applied up till now organic binding materials, on the basis of synthetic resins are characterised by good technological properties, but cause high emission of harmful substances. That’s why contemporary scientific researches are leading to progressive replacing the binders obtained from petrochemical materials with polymer biocomposites coming from renewable resources. Increasing concern of aliphatic polyesters such as polylactide, polycaprolactone, poly(hydroxyalkanoates) and aliphatic-aromatic polyesters is caused by the possibility of using them for producing many biodegradable products. In that context it is important to expand the researches connected to using biopolymers as moulding sands binders. Contemporary authors’ papers were focused on technological properties and harmfulness for the environment of this ecological moulding sands. TThis article takes into consideration the ability to reclamation of moulding sands with biopolymer binders.

One of the modern methods of the production optimisation are artificial neural networks. Neural networks owe their popularity to the fact that they constitute convenient tools, which can be applied in an extremely broad research scope. This is caused by their ability to represent complex functions. Their non-linearity should be specially emphasised. Neural networks are gaining broader and broaderapplication in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castings and supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressure castings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. The presented investigations were obtained by using the Statistica 9.0 program.The aim of the investigations was to select the neural network suitable for prediction the moulding sand moisture on the basis of thedetermined sand properties such as: permeability, compactibility, friability and compressive strength in dependence on the matrix grainsize.

The article is discussing authors examinations concerning the influence of the sulphur diffusion from moulding sand on reduction theefficiency of modifier elements in the process of making the nodular cast iron. In case of magnesium decrease of its content is observe, asa result of forming the magnesium sulphide. In consequence the participation of magnesium is falling below the concentration essential to create a spheroid graphite. The source of sulphur in no-bake sand with resin modified by furfuryl alcohol is a hardener, on the basis of sulphonic acids and sulphuric acid. Described examinations relate to no-bake sands made on the warp of fresh quartz sand.

One of the modern methods of the production optimisation are artificial neural networks. Neural networks are gaining broader and broaderapplication in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castingsand supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressurecastings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is theassessment method of sands suitability by means of detecting correlations between their individual parameters. The presentedinvestigations were obtained by using the Statistica 9.0 program. The presented investigations were aimed at the selection of the neuralnetwork able to predict the active bentonite content in the moulding sand on the basis of this sand properties such as: permeability,compactibility and the compressive strength. An application of the Statistica program allowed to select automatically the type of networkproper for the representation of dependencies occurring in between the proposed moulding sand parameters. The most advantageousconditions were obtained for the uni-directional multi-layer perception (MLP) network. Knowledge of the neural network sensitivity to individual moulding sand parameters, allowed to eliminate not essential ones.

The article takes into consideration technological and ecological aspects of IV generation moulding sands. Investigations concerning anapplication of biopolymer materials as binders for moulding sands are presented in the paper. These investigations are the continuation ofexaminations related to applications of various biopolymers as binding agents and to the properties of the moulding sands with biopolymerbinders. In the paper there are the researches concerning analyzing gases emitted from moulding sands during heating.

Investigations concerning an application of biopolymer materials as binders for moulding sands are presented in the paper. Theseinvestigations constitute the continuation of examinations related to applications of various biopolymers as binding agents. The results ofstrength tests, obtained for the investigated sands (with the PLA2 biopolymer binder) prepared in a self-hardening sands technology andair as well as microwave hardened, are presented. Examinations of sand thermal deformations based on the hot distortion measurementsand on the basis of thermogravimetric investigations of sands with selected biopolymer binders were performed.

The article presents the results of primary researches of the IV generation moulding sands, in which as the binders are used differentbiodegradable materials. The bending and the tensile strength of the moulding sands with polylactide, poly(lactic-co-glycolic acid),polycaprolactone, polyhydroxybutyrate and cellulose acetate as binders were measured. The researches show that the best strengthproperties have the moulding sands with polylactide as binder. It was proved that the tested moulding sands’ strength properties are goodenough for foundry practice.

The progressive mechanization and automation of industrial equipment is the driving force of progress, not only in the field of production but also in the measuring and control equipment. In mold production, the automation of processes such as forming molds and cores along with their assembly has led to increases in serial production, reductions in defects, and the shortening of molding times, among others. Thanks to automation in mold and core departments and the use of all sorts of manipulators, mold production in foundries has gained momentum. Unfortunately, in addition to the mentioned advantages, there are also new challenges as to the quality and properties of the molding and core sands used in highly automated foundries.This article presents recent research on molding sand elasticity. The topic was introduced as an attempt to answer the new needs of highly mechanized foundries. The article discusses a new method of measuring the resistance of molding materials to undergoing mechanical deformation (molding sand elasticity), with an additional analysis of the bending strengths of the tested samples. Precise measurements, test sample preparation, and interpretation of the received results are presented in the article.

The article takes into consideration the researches concerning inputting the new hardener to moulding sands with water glass, carried out in ester technology. Investigations are continuation of works connected to hardener based on carbonic acid’s esters, that significantly upgrades the ability of these moulding sands to mechanical reclamation. Its’ nuisance is short vitality. This is why, new investigations were taken to elaborate another hardener keeping the positive characteristics of the previous one and allowing the wider usage of technologies of loose self-hardened moulding sands with water glass.

The article concerns a trial of explaining the mechanism of improving the knock-out properties of moulding sands with water glass made in ester technology after using the new additive called Glassex. Within the labour, the variety of technological and basic researches were done, including the researches evaluating the chemical influence of the new additive.

The artictc takcs into considcrat ion the researches concerning thc possibilit ics of increasing rhc abilitics of scclnmation of 1m.w selfhardcningrnoz~ldings ands with waccr glass and liquid bzrdcncrs. Thc rescarchcs show. that thc tactor rcsponsiblc for low cfficicncy ofmechanical rcclnmnt ion of thcsc moulding sands is a cumulating of hydratcd sodium acctatc on rhc rcclairn's surfacc. which is a product ofrcaction bctwccn watcr glass and commonly used in [his ~cchnology- hardcncrs on thc basis of cstcrs of acetic acid. Thc prcscl~tcdn cwmethod is hascd on replacing thc CII rrcntly used hardcncr with an nltcrnativc hnsdcncr on tbc basis orcstcrs of carbon acid,.

The necessity of receiving high quality castings forces undertaking research to elaborate moulding and core sands ensuring obtaining the materials with relevant technological parameters and also with high environmental standards. The most important group here are moulding sands with hydrated sodium silicate. Unfortunately, their fundamental disadvantages are weak knock-out properties. The article presents the most commonly used methods of measuring the knock-out properties of moulding and core sands. The authors propose a new method for estimation this parameter. The method is based on the measurement of high-temperature expansion. Potrzeba uzyskiwania wysokiej jakości odlewów wymusza podejmowanie prac badawczych dla otrzymania mas formierskich i rdzeniowych zapewniających uzyskanie tworzyw o odpowiednich parametrach technologicznych, jednocześnie spełniających wysokie wymogi ochrony środowiska. Najważniejszą grupę stanowią tutaj masy z uwodnionym krzemianem sodu. Niestety jedną z ich podstawowych wad jest słaba wybijalność. W artykule zostały przedstawione najczęściej stosowane metody pomiaru wybijalności mas formierskich i rdzeniowych Autorzy zaproponowali nową metodę oceny wybijalności opierającą się na pomiarze ekspansji wysokotemperaturowej. Web of Science 59 2 742 739

The article takes into consideration the researches concerning inserting the Glassex additive to the microwaved-hardened and selfhardened moulding sands with water glass. In the research different types of ester hardeners to self-hardened moulding sands with water glass were used. The influence of Glassex additive on retained strength of moulding sands with different hardeners and prepared by different technologies of hardening were tested. The influence of different hardeners and the technology of hardening on retained strength of moulding sand with water glass and the Glassex additive were also estimated.

The article takes into consideration the researches concerning inserting the Glassex additive to the moulding sands with water glass and the new ester hardeners. The investigations combine the works connected to the Glassex additive influence on the moulding sand's with water glass knock-out properties and the works connected to the elaboration of the new ester hardeners upgrading of ability to mechanical reclamation of the moulding sand with water glass.