The paper presents results of measuring heat diffusivity and thermal conductivity coefficients of used green foundry sand in temperature
range ambient – 600 o
C. During the experiments a technical purity Cu plate was cast into the green-sand moulds. Basing on measurements
of the mould temperature field during the solidification of the casting, the temperature relationships of the measured properties were
evaluated. It was confirmed that the obtained relationships are complex and that water vaporization strongly influences thermal
conductivity of the moulding sand in the first period of the mould heating by the poured and solidified casting
The paper presents results of measuring thermal conductivity and heat capacity of bentonite foundry sand in temperature range ambient –
900 OC. During the experiments a technical purity Cu plate was cast into the green-sand moulds. Basing on measurements of the mould
temperature field during the solidification of the casting, the temperature relationships of the measured properties were evaluated. It was
confirmed that water vaporization strongly influences thermal conductivity of the moulding sand in the first period of the mould heating by
the poured casting.
Along with the increase in popularity of the sewage sludge thermal treatment methods in Poland
resulting from the implementation of European Union law, a management problem with ash, which is produced
as a result of this process, appeared. The paper analyses the chemical composition and physical properties of fl y
ash from thermal treatment of municipal sewage sludge in terms of its use in concrete technologies in relation to
EN 450-1 Fly ash for concrete. Defi nition, specifi cations and conformity criteria (2012) and EN 197-1 Cement.
Composition, specifi cations and conformity criteria for common cements (2011) standards. The tested material did
not meet the requirements related to use of fl y ash for concrete production (chemical composition, low activity
index, high water demand and fi neness), and as main and minor components for cement production. On the basis
of the carried out research and analyses, it was found that the hardening slurry technology creates the greatest
possibilities related to the management of fl y ash from thermal treatment of municipal sewage sludge.
AISI 316L/TiB2/2p composites were manufactured by HP-HT using different pressures (5 and 7 GPa) and temperatures (900-1300°C), with constant reinforcing particle content 2 vol%. The mechanical properties of the composites were evaluated on the basis of hardness (HV0.3) and compression tests (20°C, 10−5 s−1). The results showed that the role of sintering pressure increased with increasing process temperature. At temperatures of 900°C and pressures of 5 and 7 GPa the difference in measured values of compressive strength was 1-2%, while at 1300°C they reached 20%. At constant pressure of 5 GPa, a change in hardness and compressive strength of 40% were obtained with a temperature change of 900 to 1300°C. Changes in mechanical properties in the composite occurred without substantial changes in density, microstructure, reinforcement phase distribution, and phase composition in the matrix.
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