This study summarises the research efforts undertaken in iron foundry plants in which the process are mostly automated and mechanised.

The research program was limited in scope, focusing on causes of surface defects in castings products that are attributable to the

bentonite-containing sand and the mould system. One of the potential roots of surface defects is heterogeneity of sand grains, containing

lumped ball-shaped grains and irregular pellets with a layered-structure. The moisture contents of those lumped grains is different than

the moisture level required in the process, besides these grains may contain various elements and metallic compounds which, when cast

into moulds, may react with molten metals in an uncontrolled manner. As a result, surface defects are produced, such as surface blowholes,

burst penetration, sand holes, slag inclusions, pinhole porosity. This study investigated the efficiency of key sand preparation and

moulding machines and installations integrated into the casting process line. The efficiency of machines and installations is defined in

terms of quality parameters of sand mix and moulds, which are associated with the emergence of surface defects on castings.

Definition of a composite [1] describes an ideal composite material with perfect structure. In real composite materials, structure is usually imperfect – composites contain various types of defects [2, 3–5], especially as the casted composites are of concern. The reason for this is a specific structure of castings, related to course of the manufacturing process. In case of metal matrix composite castings, especially regarding these manufactured by saturation, there is no classification of these defects [2, 4]. Classification of defects in castings of classic materials (cast iron, cast steel, non-ferrous alloys) is insufficient and requires completion of specific defects of mentioned materials. This problem (noted during manufacturing metal matrix composite castings with saturated reinforcement in Institute of Basic Technical Sciences of Maritime University Szczecin) has become a reason of starting work aimed at creating such classification. As a result, this paper was prepared. It can contribute to improvement of quality of studied materials and, as a consequence, improve the environment protection level.

The authors developed the definition of construction defect and fault and construction defect management based on Polish and foreign publications. In order to assist identification of faults and their analysis in the process of home collection, the authors applied the Case Based Reasoning (CBR) method. In the paper, the authors used Case Based Reasoning (CBR) to support acceptance of apartments. The CBR method allows to determine the magnitude of global similarity for the problem under consideration between the new and old case from the Case Base, using weighted sums of local similarities using criteria weights as coefficients. As a result of CBR-based solutions, an Employer’s representative receives information about the type of construction defects that can be expected, their location and significance, occurrence frequency, and estimated repair cost.

The powerful tool for defect analysis is an expert system. It is a computer programme based on the knowledge of experts for solving the

quality of castings. We present the expert system developed in the VSB-Technical University of Ostrava called ‘ESWOD’. The ESWOD

programme consists of three separate modules: identification, diagnosis / causes and prevention / remedy. The identification of casting

defects in the actual form of the system is based on their visual aspect.

Diagnostics of composite castings, due to their complex structure, requires that their characteristics are tested by an appropriate description

method. Any deviation from the specific characteristic will be regarded as a material defect. The detection of defects in composite castings

sometimes is not sufficient and the defects have to be identified. This study classifies defects found in the structures of saturated metallic

composite castings and indicates those stages of the process where such defects are likely to be formed. Not only does the author

determine the causes of structural defects, describe methods of their detection and identification, but also proposes a schematic procedure

to be followed during detection and identification of structural defects of castings made from saturated reinforcement metallic composites.

Alloys examination was conducted after technological process, while using destructive (macroscopic tests, light and scanning electron

microscopy) and non-destructive (ultrasonic and X-ray defectoscopy, tomography, gravimetric method) methods. Research presented in

this article are part of author’s work on castings quality.

In our study, we estimated the frequency of haplotype for cholesterol deficiency (HCD) carriers in the Russian Holstein cattle population. We studied 1817 random samples of cows born in 2010-2017 from ten herds and 331 cows and heifers from the other three herds born in 2016-2019, fathers or fathers of mothers of which were HCD carriers. The method of AS-PCR was used for animals genotyping. In the first group of animals, the incidence of HCD carriers was 8.09%, and in the second one - 23.26%. Our results demonstrated the necessity to test cows for the carriage of the HCD genetic defect in the Russian population of Holstein cattle.

A group of old apartment houses with the age over 100 years (that is those carried out before the First World War) takes an important place in polish building resources. Technical maintenance of apartment houses, traditional methods erected, is nowadays and will be a valid problem in the nearest future. The results of the work refer to the general population, estimated for 600 objects, that is about 20% of municipal downtown apartment houses in Wrocław.

The purpose of the research was to identify an influence of widely considered maintenance of apartment houses on a degree and intensity of their elements’ deterioration. The goal of the work has been fulfilled by symptoms’ analysis of declining of inspected elements’ exploitation values, that is identification of mechanics of their defects arising.

The range of the work has required creation of original qualitative model of pinpointed defects and its transfer into quantitative one. It has made possible to analyse the reason - effect phenomena „defect - technical wear” relevant to the most important elements of Wroclaw downtown district’s apartment houses. The research procedure has been conducted in accordance of fuzzy sets theory which made possible to describe qualitative model of pinpointed defects and its transfer into a quantitative one.

Effect of annealing on the structural properties of arsenic-implanted mercury cadmium telluride film grown by molecular beam epitaxy was studied with the use of transmission electron microscopy and optical reflection. Strong influence of the graded-gap surface layer grown on top of the film on the behaviour of implantation-induced defects under arsenic activation annealing was revealed and interpreted.

Changes of gas pressure in the moulding sand in the zone adjacent to mould cavity were analysed during pouring of cast iron. No significant effect of pressure on the surface quality of castings was observed. In the second series of tests, the concentration of hydrogen in the gas atmosphere was measured. It has been found that the value of this concentration depends on metal composition and is particularly high in cast iron containing magnesium. This is due to the reduction of water vapour with the element that has high affinity to oxygen. The presence of hydrogen causes the formation of gas-induced defects on the casting surface.

The chosen, typical causes of quality defects of cast-iron „alphin” rings embedded in aluminum cast are being presented in this paper.

Diffusive joint of those inserts with the pistons casts is being used, due to extreme work conditions of destructive influence of the fuel mix

and variable thermo-mechanical loads, which reign in the combustion motor working chamber.

Foundry technologists use their own style of gating system designing. Most of their patterns are caused by experience. The designs differ from plant to plant and give better or worse results. This shows that the theory of gating systems is not brought into general use sufficiently and therefore not applied in practise very often. Hence, this paper describes the theory and practical development of one part of gating systems - sprue base for automated horizontal moulding lines used for iron castings. Different geometries of sprue bases with gating system and casting were drawn in Solid Edge ST9. The metal flow through the gating systems was then simulated with use of MAGMA Express 5.3.1.0, and the results were achieved. The quality of flow was considered in a few categories: splashes, air entrapment, vortex generation and air contact. The economical aspect (weight of runner) was also taken under consideration. After quantitative evaluation, the best shape was chosen and optimised in other simulations with special attention on its impact on filling velocity and mould erosion. This design (a sprue base with notch placed in drag and cope) is recommended to be used in mass production iron foundries to reduce oxide creation in liquid metal and especially to still metal stream to improve filtration.

Simulation software can be used not only for checking the correctness of a particular design but also for finding rules which could be used

in majority of future designs. In the present work the recommendations for optimal distance between a side feeder and a casting wall were

formulated. The shrinkage problems with application of side feeders may arise from overheating of the moulding sand layer between

casting wall and the feeder in case the neck is too short as well as formation of a hot spot at the junction of the neck and the casting. A

large number of simulations using commercial software were carried out, in which the main independent variables were: the feeder’s neck

length, type and geometry of the feeder, as well as geometry and material of the casting. It was found that the shrinkage defects do not

appear for tubular castings, whereas for flat walled castings the neck length and the feeders’ geometry are important parameters to be set

properly in order to avoid the shrinkage defects. The rules for optimal lengths were found using the Rough Sets Theory approach,

separately for traditional and exothermic feeders.

Simulation software dedicated for design of casting processes is usually tested and calibrated by comparisons of shrinkage defects

distribution predicted by the modelling with that observed in real castings produced in a given foundry. However, a large amount of

expertise obtained from different foundries, including especially made experiments, is available from literature, in the form of

recommendations for design of the rigging systems. This kind of information can be also used for assessment of the simulation predictions.

In the present work two parameters used in the design of feeding systems are considered: feeding ranges in horizontal and vertical plates as

well as efficiency (yield) of feeders of various shapes. The simulation tests were conducted using especially designed steel and aluminium

castings with risers and a commercial FDM based software. It was found that the simulations cannot predict appearance of shrinkage

porosity in horizontal and vertical plates of even cross-sections which would mean, that the feeding ranges are practically unlimited. The

yield of all types of feeders obtained from the simulations appeared to be much higher than that reported in the literature. It can be

concluded that the feeding flow modelling included in the tested software does not reflect phenomena responsible for the feeding processes

in real castings properly. Further tests, with different types of software and more fundamental studies on the feeding process modelling

would be desirable.