Gases Emission From Surface Layers of Sand Moulds and Cores Stored Under the Humid Air Conditions

Open access


A large number of defects of castings made in sand moulds is caused by gases. There are several sources of gases: gases emitted from moulds, cores or protective coatings during pouring and casting solidification; water in moulding sands; moisture adsorbed from surroundings due to atmospheric conditions changes. In investigations of gas volumetric emissions of moulding sands amounts of gases emitted from moulding sand were determined - up to now - in dependence of the applied binders, sand grains, protective coatings or alloys used for moulds pouring. The results of investigating gas volumetric emissions of thin-walled sand cores poured with liquid metal are presented in the hereby paper. They correspond to the surface layer in the mould work part, which is decisive for the surface quality of the obtained castings. In addition, cores were stored under conditions of a high air humidity, where due to large differences in humidity, the moisture - from surroundings - was adsorbed into the surface layer of the sand mould. Due to that, it was possible to asses the influence of the adsorbed moisture on the gas volumetric emission from moulds and cores surface layers by means of the new method of investigating the gas emission kinetics from thin moulding sand layers heated by liquid metal. The results of investigations of kinetics of the gas emission from moulding sands with furan and alkyd resins as well as with hydrated sodium silicate (water glass) are presented. Kinetics of gases emissions from these kinds of moulding sands poured with Al-Si alloy were compared.

[1] Falęcki, Z. (1997). Analysis of casting defects. Kraków: Wydawnictwo AGH. (in Polish).

[2] PN-85/H-83105, Castings - division and terminology of defects.

[3] Hiremath, S.S. & Dulange, S.R. (2015). Advanced techniques in casting defects and rejection analysis: a study in a industry. International Journal of Innovations in Engineering Research and Technology. 2(9), 364-371.

[4] Davis, J.R. (Eds.) (1996). Casting Defects, Nondestructive Inspection, and Quality Control Measures. In: ASM Specialty Handbook Cast Iron (287-321). Ohio: ASM International.

[5] Rowley, M.T. (Eds.). (1974). International atlas of foundry defects. International Committee of Foundry Technical Associations. Committee of Metallurgy and Foundry Properties. English Edition.

[6] Fruehan, R.J. (1988). The thermodynamics and kinetics of gas dissolution and evolution from iron alloys. In: Foundry Processes: Their Chemistry and Physics (pp. 411-426). New York: Plenum Press.

[7] Kaźnica, N. & Zych, J. (2015). Investigations of the sorption process' kinetics of sand moulds' surface layers under conditions of a high air humidity. Archives of Foundry Engineering. 15 (spec.3), 29-32.

[8] Kaźnica, N. & Zych, J. (2015). Moisture sorption and desorption processes on the example of moulding sands' surface layers. Archives of Foundry Engineering. 15(4), 63-66. (in Polish).

[9] Kaźnica, N. & Zych, J. (2017). Role of sand grains in sorption processes by surface layers of components of sand moulds. Archives of Foundry Engineering. 17(1), 87-92.

[10] Sarkar, A.D. (1967). Sand Testing (pp. 5-19). In: Mould & Core Material for the Steel Foundry. Oxford: Pergamon.

[11] Lewandowski, J.L., Solarski, W. & Pawłowski, Z. (1993). Classification of moulding and core sands in terms of gas emission. Przegląd Odlewnictwa. 5, 143-149. (in Polish).

[12] Zych, J., Mocek, J. & Snopkiewicz, T. (2014). Gas generation properties of materials used in the sand mould technology - modified research method. Archives of Foundry Engineering. 14(3), 105-109.

[13] Zhang, B., Garro, M., Chautard, D. & Tagliano, C. (2002) Gas evolution from resin - bonded sand cores prepared by various processes. Metallurgical Science and Technology. 20(2), 27-33.

[14] Godding, R.G. (1962). Measurement of gas evolution from core sand. British Cast Iron Research Association Journal. 9, 687-692.

[15] Holtzer, M., Kwaśniewska-Królkowska, D., Bobrowski, A., Dańko, R., Grabowska, B., Żymankowska-Kumon, S. & Solarski, W. (2012). Investigations of a harmful components emission from moulding sands with bentonite and lustrous carbon carriers when in contact with liquid metals. Przegląd Odlewnictwa. 62 (3-4), 124-132. (in Polish).

[16] Bobrowski, A., Holtzer, M., Dańko, R. & Żymankowska- Kumon, S. (2013). Analisys of gases emitted during a thermal decomposition of the selected phenolic binders. Metalurgia International. 18 (spec.7), 259-261.

[17] Holtzer, M., Dańko, J., Lewandowski, J.L. et al. (2012). Station for research of the volume and harmfulness of gases compounds from the materials used in foundry and metallurgical processes. AGH Polska Patent PL 398709 A1.

[18] Holtzer, M., Dańko, R., Dańko, J., Kubecki, M., Żymankwska-Kumon, S., Bobrowski, A., Śpiewok, W. (2013). The assesment of harmfulness of binding materials used for a new generation of core and molding sands. Kraków: Wydawnictwo Naukowe Akapit (in Polish).

[19] Winardi, L., Littleton, H., Bates, C.E. (2007). Variables Affecting Gas-Evolution Rates from Cores in Contact with Aluminum. Foundry Management & Technology.

[20] Winardi, L., Weiss, D., Scarber, P. Jr ., Griffin, R.D. (2008). Comparison of Gas Evolution Results from Chemically Bonded Cores in Contact with Magnesium and Aluminum Melts. AFS Transactions. 116, 769-783.

[21] Winardi, L., Griffin, R.D., Littleton, H.E., Griffin, J.A. (2008). Variables Affecting Gas Evolution Rates and Volumes from Cores in Contact with Molten Metal. AFS Transactions. 116, 505-521.

[22] Scarber, Jr. P., Bates, C.E. & Griffin, J.A. (2006). Effects of Mold and Binder Formulations on Gas Evolution When Pouring Aluminum Castings. AFS Transactions. 114.

[23] Zych, J., Mocek, J. (2016). Gas generation the top layer of sand mould. In: Nauka i technika w inżynierii procesów odlewniczych (pp. 65-78), Kraków: Wydawnictwo Naukowe AKAPIT. (in Polish).

[24] Zych, J., Mocek, J. & Kaźnica, N. (2017). Kinetics of Gases Emission from Surface Layers of Sand Moulds, Archives of Foundry Engineering, in print.

Archives of Foundry Engineering

The Journal of Polish Academy of Sciences

Journal Information

CiteScore 2016: 0.42

SCImago Journal Rank (SJR) 2016: 0.192
Source Normalized Impact per Paper (SNIP) 2016: 0.316


All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 131 131 11
PDF Downloads 61 61 10