Pattern evaporation process

• Autorzy: Żółkiewicz Z. , Żółkiewicz M.
• Języki publikacji: EN

Abstrakty

EN

The paper discusses the process of thermal evaporation of a foundry pattern. At several research-development centres, studies have been carried out to examine the physico-chemical phenomena that take place in foundry mould filled with polystyrene pattern when it is poured with molten metal. In the technique of evaporative patterns, the process of mould filling with molten metal (the said mould holding inside a polystyrene pattern) is interrelated with the process of thermal decomposition of this pattern. The transformation of an evaporative pattern (e.g. made from foamed polystyrene) from the solid into liquid and then gaseous state occurs as a result of the thermal effect that the liquid metal exerts onto this pattern. Consequently, at the liquid metal-pattern-mould phase boundary some physico-chemical phenomena take place, which until now have not been fully explained. When the pattern is evaporating, some solid and gaseous products are evolved, e.g. CO, CO2, H2, N2, and hydrocarbons, e.g. styrene, toluene, ethane, methane, benzene [16, 23]. The process of polystyrene pattern evaporation in foundry mould under the effect of molten metal is of a very complex nature and depends on many different factors, still not fully investigated. The kinetics of pattern evaporation is also affected by the technological properties of foundry mould, e.g. permeability, thermophysical properties, parameters of the gating system, temperature of pouring, properties of pattern material, and the size of pattern-liquid metal contact surface.

Słowa kluczowe

EN

casting; pattern; pattern made of foamed polystyrene; temperature; gas; evaporation

PL

odlew; model; model z polistyrenu; temperatura; odparowanie

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2007
• Tom: Vol. 7, iss. 2
• Strony: 49--52
• Opis fizyczny: Bibliogr. 11 poz., rys.

Twórcy

autor

Żółkiewicz Z.

autor

Żółkiewicz M.

• Foundry Research Institute, Zakopiańska Str. 73, 31- 418 Kraków,

Bibliografia

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• [5] Šuljak V.S.: Sostoianie lit'ja po gazificiruemym modeljam za rubiezom (Odlewanie technologią modeli zgazowanych za granicą), Litejnoe Proizvodstvo 1991, nr 1, s. 21 - 23,
• [6] Wilk J., Żółkiewicz Z.: Determination of optimum Technology in Respect of the Required Values of Casting Quality Parameters by Aplication of the Weighted Variables Metric. Materials Enginering, Slovakia 2006, t.13, nr. 3, s. 89,
• [7] Żółkiewicz Z.. Żółkiewicz M., Jankowski W., Wilk J.: Sterowanie procesem krzepnięcia odlewu w technologii modeli cieplnie zgazowywanych. Archives of Foundry - Archiwum Odlewnictwa 2006, rocznik 6, nr 18 ref. 119/18 s..219,
• [8] Żółkiewicz Z., Jankowski W.: Effect of temperature on the evaporation time of foamed polystyrene pattern. Acta Metallurgica Slovaca 7, 2001, nr.3 (1/2), s.309 - 314,
• [9] Żółkiewicz Z., Jankowski W.: Effect of the density on the rate of gas emission from polystyrene pattern in the lost foam process. PAN, Krzepnięcie Metali i Stopów, Rocznik 43, 2000, nr 2, referat 43/63 s. 553 - 560,
• [10] Żółkiewicz Z., Jankowski W.: Vliv teploty na rychlost uvolnovani plynu z polystyrenovych modelu pri postupu liti do plnych forem, Slevarenstvi 2000, Vol.XLVIII, nr 4, s.192-194,
• [11] Żółkiewicz Z., Jankowski W., Wacławik Z.: Effect of temperature on the volume and rate of gas emissions from polystyrene pattern evaporated in the full mould process. Archives of Metallurgy, Kraków 1999, t.44, nr.1, s. 111 - 118.