The paper presents results of calorimetric studies of foundry nickel superalloys: IN100, IN713C, Mar - M247 and ŻS6 U. Particular attention was paid to determination of phase transiti ons temperatures during heating and cooling. The samples were heated to a temperature of 1500°C with a rate of 10°C ⋅ min – 1 and then held at this temperature for 5 min. After a complete melting, the samples were cooled with the same rat e. Argon with a purity of 99.99% constituted the protective atmosphere. The sample was placed in an alundum crucible with a capacity of 0.45 cm 3 . Temperature and heat calibration was carried out based on the mel ting point of high- purity Ni. The tests were carried out by the differential scanning calorimetry (DSC) using a Multi HTC high -temperature calorimeter from Setaram. Based on the DSC curves, the following temperatures were determined: solidus and liquidus, dissolution and precipitation of the γ ’ phase, MC carbides and melting of the γ ’ /γ eutectic. In the temperature range of 100 -1100°C, specific heat capacity of the investigated superalloys was determined. It was found that the IN713C and IN100 alloys exhibit a higher specific heat while compared to the Mar - M247 and ŻS6 U alloys.
The study presents the results of the investigations of the effect of Cu, Ni, Cr, V, Mo and W alloy additions on the microstructure and
mechanical properties of the AlSi7Mg0.3 alloy. The examinations were performed within a project the aim of which is to elaborate an
experimental and industrial technology of producing elements of machines and devices complex in their construction, made of aluminium
alloys by the method of precision investment casting. It was demonstrated that a proper combination of alloy additions causes the
crystallization of complex intermetallic phases in the silumin, shortens the SDAS and improves the strength properties: Rm, Rp0.2,HB
hardness. Elevating these properties reduces At, which, in consequence, lowers the quality index Q of the alloy of the obtained casts.
Experimental casts were made in ceramic moulds preliminarily heated to 160 °C, into which the AlSi7Mg0.3 alloy with the additions was
cast, followed by its cooling at ambient temperature. With the purpose of increasing the value of the quality index Q, it is recommended
that the process of alloy cooling in the ceramic mould be intensified and/or a thermal treatment of the casts be performed (ageing)(T6).
The study discusses the issues connected with the production of thin-walled ceramic slurry in the replicast cs technology. In the ceramic mould production process, a special role is played by the liquid ceramic slurry used to produce the first layer of the mould. The study examines selected technological properties of liquid ceramic slurries used to produce moulds in the replicas cs technology. The ceramic slurries for the tests were prepared based on the binders Ludox Px30 and Sizol 030, enriched with Refracourse flour. The wettability of the pattern's surface by the liquid ceramic slurry and the dependence of the apparent viscosity on the ceramic flour content in the mixture were determined. The wettability of the pattern surface by the liquid ceramic slurry was determined based on the measurement of the wetting angle. The angle was determined by means of an analysis of the computer image obtained with the use of a CDC camera.
The paper presents the use of rapid prototyping technology of three dimensional printing (3DP) to make a prototype shell casting mold. In
the first step, for identification purposes, a mold was prepared to enable different alloys to be cast. All molds being cast were designed in a
universal CAD environment and printed with the zp151 composite material (Calcium sulfate hemihydrate) with a zb63 binder (2-
pyrrolidone). It is designated to be used to prepare colourful models presenting prototypes or casting models and molds. The usefulness of
3DP technology for use with copper alloys, aluminum and zinc was analyzed. The strength of the mold during casting was assumed as a
characteristic comparative feature in the material resistance to high temperature, the quality of the resulting casting and its surface
roughness. Casting tests were carried out in vacuum – pressure casting. The casting programs applied, significantly increased the quality of
castings and enabled precise mold submergence. Significant improvement was noted in the quality compared to the same castings obtained
by gravity casting.
A special Slag-Prop Cu database has been developed to archive data from laboratory and industrial tests related to post-reduction slags. In
order to enrich the data areas, it was decided to design a system for measuring the temperature of the liquid slag and its viscosity. Objectives
of research work are to gather information on the properties of post-slags such as the temperature of liquid slag and its viscosity. The
discussed issues are especially important in the foundry practice. Designed research stand and using of database applications can greatly
facilitate the work of metallurgists, foundrymen, technologists and scientists. The viscosity measurement was developed and presented
earlier. The author's analytical methodology was supplemented by a thyristor measuring system (described in the article). The system
temperature measurement can be performed simultaneously in 3 ways to reduce the measurement error. Measurement of the voltage mV -
using the Seebeck effect can be measured throughout the entire range of thermocouple resistance, up to 1300 °C. Direct temperature
measurement ⁰C - measurement only below 1000 ⁰C. Additional measurement - the measurement can also be read from the pyrometer set
above the bath. The temperature and the reading frequency depend on the device itself. The principle of measurement is that in a molten
metal / slag crucible, we put a N-type thermocouple. The thermocouples are hung by means of a tripod above the crucible and placed in a
crucible. The thermocouple is connected to a compensating line dedicated to this type of thermocouple. The cable is in turn connected to a
special multimeter that has the ability to connect to a computer and upload results. Temperature measurement can be performed
simultaneously in 3 ways to reduce the measurement error. The Sn-Pb alloy has been subjected to testing for proper operation of the device.
In this foot should be observed the supercooling of the liquid, which initiates the crystallization process and in which latent heat begins to
exude raising the temperature until the coagulation temperature is reached.
In highly developed countries, a significant progress in the use of alternative and clean energy sources has recently been observed. The
European Union has implemented a programme to build wind turbines. It is estimated that in the coming years, thanks to the support in tax
and credit, the global energy will develop very intensively.
Many components of the wind turbines are castings. The basic material used for these castings is ductile iron, which in this particular case
must meet high requirements imposed by the operating conditions of wind turbines. Anticipating an increase in customer demand for this
type of castings, Krakodlew SA has decided to modernize its foundry using the ability to obtain external financing.
The ductile iron manufacturing technology is now being developed and adapted to the specific conditions of the foundry plant, including
the melting process yielding cast material with the required chemical composition, the technology of moulding, and the conditions for
possible secondary metallurgy, spheroidizing treatment and graphitizing inoculation. The fulfilment of the imposed conditions for the
casting production demands the use of advanced casting technologies introduced to the manufacturing process.
The development of technology to launch the production of ductile iron castings for the wind power industry was supported by The
National Centre for Research and Development (NCBiR). This article presents part of research on the binding kinetics of furan resin sands
and choice of their composition for moulds and cores to make heavy castings used as components of equipment for the wind power
industry.
Small additions of Cr, Mo and W to aluminium-iron-nickel bronze are mostly located in phases κi (i=II; III; IV),and next in phase α
(in the matrix) and phase γ2. They raise the temperature of the phase transformations in aluminium bronzes as well as the casts’ abrasive
and adhesive wear resistance. The paper presents a selection of feeding elements and thermal treatment times which guarantees structure
stability, for a cast of a massive bush working at an elevated temperature (650–750°C) made by means of the lost foam technology out of
composite aluminium bronze. So far, there have been no analyses of the phenomena characteristic to the examined bronze which
accompany the process of its solidification during gasification of the EPS pattern. There are also no guidelines for designing risers and
steel internal chill for casts made of this bronze. The work identifies the type and location of the existing defects in the mould’s cast. It also
proposes a solution to the manner of its feeding and cooling which compensates the significant volume contraction of bronze and
effectively removes the formed gases from the area of mould solidification. Another important aspect of the performed research was
establishing the duration time of bronze annealing at the temperature of 750°C which guarantees stabilization of the changes in the bronze
microstructure – stabilization of the changes in the bronze HB hardness.
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