Archives of Foundry Engineering

Casting is the most widely used manufacturing technique. Furan No-bake mould system is very widely accepted in competitive foundry

industries due to its excellent characteristics of producing heavy and extremely difficult castings. These castings have excellent surface

finish and high dimensional stability. Self setting and high dimensional stability are the key characteristics of FNB mould system which

leads to reduce production cycle time for foundry industries which will ultimately save machining cost, labour cost and energy.

Compressive strength is the main aspect of furan no bake mould, which can be improved by analyzing the effect of various parameters on

it. ANN is a useful technique for determining the relation of various parameters like Grain Fineness Number, Loss on Ignition, pH, % resin

and temperature of sand with compressive strength of the FNB mould. Matlab version: R2015a version 8.3 software with ANN tool box

can be used to gain output of relation. This paper deals with the representation of relationship of various parameters affecting on the

compressive strength of FNB mould

The purpose of this study was to establish a relationship between the type of wall connection used in the cast grates, which are part of the

equipment operating in furnaces for heat treatment and thermal-chemical treatment, and stresses generated in these grates during the

process of rapid cooling. The places where the grate walls are connected to each other are usually characterized by the thickness larger

than the remaining parts of walls. Temperature variations in those places are responsible for the formation of hot spots, and in the hot spots

temperature changes much more slowly. The type of wall connection shapes the temperature gradient in the joint cross-section, and hence

also the value of thermal stresses generated during cooling. In this study, five different designs of the grates were compared; the difference

in them was the type of the designed wall connection. The following design variants were adopted in the studies: X connections with and

without holes, T connections with and without technological recesses, and R (ring) connection. Numerical analysis was performed to

examine how the distribution of temperature changes in the initial phases of the cooling process. The obtained results served next as a tool

in studies of the stress distribution in individual structures. The analysis were carried out by FEM in Midas NFX 2014 software. Based on

the results obtained, the conclusions were drawn about the impact of different types of wall connections on the formation of thermal

stresses in cast grates.

The most important feature of bells is their sound. Its clarity and beauty depend, first of all, on the bell’s geometry - particularly the shape

of its profile, but also on the quality of alloy used to its cast. Hence, if the melting and pouring parameters could influence the alloy’s

properties, what influence they would have on the frequencies of bell’s tone. In the article authors present their own approaches to find

answers on that and more questions.

The surfacing technologies are used for constitution of protection layer against wear and is destined for obtaining coating with high

hardness. Among many weldings methods currently used to obtain the hard surface layer one of the most effective way of hardfacing is

using flux cored arc welding. This additional material gives more possibilities to make expected hard surface layer.

Chemical composition, property and economic factors obtained in flux cored wire are much richer in comparison to these obtained with

other additional materials. This is the reason why flux cored wires give possibilities of application this kind of material for improving

surface in different sectors of industry.

In the present paper the imperfection in the layers was used for hardfacing process in different situations to show the possible application

in the surface layer. The work presents studies of imperfection of the welds, contains the picture of microstructures, macrostructures and

shows the results of checking by visual and penetrant testing methods.

In this paper an attempt to determine the relationship between the electrical resistivity and the tensile strength and hardness of cast iron of

carbon equivalent in the range from 3.93% to 4.48%. Tests were performed on the gray cast iron for 12 different melts with different

chemical composition. From one melt poured 6 samples. Based on the study of mechanical and electro-resistive determined variation

characteristics of tensile strength, hardness and resistivity as a function of the carbon equivalent. Then, regression equations were

developed as power functions describing the relationship between the resistivity of castings and their tensile strength and hardness. It was

found a high level of regression equations to measuring points, particularly with regard to the relationship Rm=f(ρ). The obtained

preliminary results indicate the possibility of application of the method of the resistance to rapid diagnostic casts on the production line,

when we are dealing with repeatable production, in this case non variable geometry of the product for which it has been determinated

before a regression equation.

The article presents research results of physico-chemical and environmental issues for the dust generated during dedusting of the

installation for the processing and preparation of moulding sand with bentonite. Particular attention was paid to the content of heavy

metals and emission of gases from the BTEX group, which is one of the determinants of the moulding sands harmfulness for the

environment. The analysis of heavy metals in the test samples indicate that there is an increase of the content of all metals in the dust

compared to the initial mixture of bentonite. The most significant (almost double) increase observed for zinc is probably related to the

adsorption of this element on the dust surface by contact with the liquid metal. The study showed, that dust contained more than 20% of

the amount of montmorillonite and had a loss on ignition at a similar level. The addition of 1% of dust to the used moulding sand results in

almost 30% increase in the total volume of gases generated in casting processes and nearly 30% increase of the benzene emission.

This paper discusses the mechanical properties of a material fabricated from commercially available metal powder mixtures designed for

use as a metal matrix of diamond impregnated composites. The mixtures with the catalogue numbers CSA and CSA800 provided by a

Chinese producer are suitable for experimental laboratory testing. The specimens were fabricated in a graphite mould using hot pressing.

The material was tested for density, porosity, hardness, and tensile strength under static loading. A scanning electron microscope (SEM)

was used to analyze the microstructure and cleavage fracture of broken specimens. It was essential to determine how the chemical

composition and the fabrication process affected the microstructure and properties of the material. The properties of the sinters were

compared with those of hot pressed specimens fabricated from sub-micron size cobalt powder (Cobalt SMS). Although the as-consolidated

material is inferior to cobalt, it displays a favourable combination of hardness, yield strength and ductility, and seems to have a great

potential for moderate and general purpose applications.

The scope of work included the launch of the process of refining slag suspension in a gas oven using a variety of technological additives.

After the refining process (in the context of copper recovery), an assessment of the effect of selected reagents at the level of the slag

refining suspension (in terms of copper recovery). Method sieve separated from the slag waste fraction of metallic, iron - silicate and

powdery waste. Comparison of these photographs macroscopic allowed us to evaluate the most advantageous method of separating

metallic fraction from the slag. After applying the sample A (with KF2 + NaCl) we note that in some parts of the slag are still large

amounts of metallic fraction. The fraction of slag in a large majority of the elements has the same size of 1 mm, and a larger portion of the

slag, the size of which is from 2 to 6 mm. Definitely the best way is to remove the copper by means of the component B (with NaCl ) and

D (with KF2

). However, as a result of removing the copper by means of component C (with CaO) were also obtained a relatively large

number of tiny droplets of copper, which was problematic during segregation. In both cases we were able to separate the two fractions in a

fast and simple manner.

The dry sliding wear behavior of heat-treated super duplex stainless steel AISI 2507 was examined by taking pin-on-disc type of wear-test

rig. Independent parameters, namely applied load, sliding distance, and sliding speed, influence mainly the wear rate of super duplex

stainless steel. The said material was heat treated to a temperature of 850°C for 1 hour followed by water quenching. The heat treatment

was carried out to precipitate the secondary sigma phase formation. Experiments were conducted to study the influence of independent