Influence of Runner Geometry on the Gas Entrapment in Volume of Pressure Die Cast

• Autorzy: Majernik J. , Podařil M.

Identyfikatory

DOI

10.24425/afe.2019.129626

• Języki publikacji: EN

Abstrakty

EN

The high pressure die casting technology allows the production of complex casts with good mechanical properties, with high production repeatability within narrow tolerance limits. However, the casts are somewhat porous, which may reduce their mechanical properties. There are several recommendations for reducing the porosity of casts, which are aimed at setting the technological parameters of the casting cycle. One of the primary and important ways to reduce the porosity and air entrapment in the melt is a suitable gating system design. Submitted contribution is devoted to assessing the influence of the runner branching geometry on the air entrapment within the cast volume during the filling phase of the casting cycle. Four variants of the gating system for a particular cast are compared with different design of main runner branching. The initial design is based on a real gating system where the secondary runner is connected to the main runner at an angle of 90 °. The modified designs are provided with a continuous transition of the main runner into the secondary ones, with the change in the branching runner radius r1 = 15 mm, r2 = 25 mm and r3 = 35 mm. The air entrapment in the melt is assessed within the cast volume behind the cores, which have been evaluated as a critical points with respect to further mechanical treatment. When designing the structural modification of geometry it was assumed that by branch changing using the radius value r3 = 35 mm, the melt flows fluently, and thus the value of the entrapped air in the volume of the cast will be the lowest. This assumption was disproved. The lowest values of entrapped air in the melt were found in the casts with runner transition designed with radius r1 = 15 mm. The conclusion of the contribution explains the causes of this phenomenon and from a designing point of view it presents proposal for measures to reduce the entrapment of the air in casts.

Słowa kluczowe

EN

HPDC; high pressure die casting; runner dimensions; air entrapment; product development; melt flow

PL

odlew wysokociśnieniowy; rynna; uwięzione powietrze; przepływ stopu

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2019
• Tom: iss. 4
• Strony: 33--38
• Opis fizyczny: Bibliogr. 12 poz., rys., tab.

Twórcy

autor

Majernik J.

• Institute of Technology and Business in České Budějovice, České Budějovice, Czech Republic

autor

Podařil M.

• Institute of Technology and Business in České Budějovice, České Budějovice, Czech Republic

Bibliografia

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• [2] Majidi, S.H. & Beckermann, C. (2019). Effect of Pouring Conditions and Gating System Design on Air Entrainment During Mold Filling. International Journal of Metalcasting. 13(2), 255-272. DOI: 10.1007/s40962-018-0272-x.
• [3] Majerník, J. (2019). The issue of the gating system design for permanent die (Problematika návrhu vtokových soustav permanentních forem pro litíkovů pod tlakem). Stalowa Wola: Wydawnictwo Sztafeta Sp. z.o.o.
• [4] Iwata, Y. et al.. (2012). Compression behavior of entrapped gas in high pressure diecasting. Materials Transactions. 53(3), 483-488. DOI: 10.2320/matertrans.F-M2011858.
• [5] Gaspar, S. & Pasko, J. (2016). Pressing Speed, Specific Pressure and Mechanical Properties of Aluminium Cast. Archives of Foundry Engineering. 16(2), 45-50. DOI: 10.1515/afe-2016-0024.
• [6] Iwata, Y. et al.. (2013). Effects of solidification behavior during filling on surface defects of aluminum alloy die casting+. Materials Transactions. 54(10), 1944-1950. DOI: 10.2320/matertrans.F-M2013819.
• [7] Paško, J., Gašpár, Š. (2014). Technological Factors of Die Casting. Lüdenscheid: RAM-Verlag.
• [8] Kanazawa, K., Yano, K., Kawatani, R., Ogura, J., Nemoto, Y. (2016). Optimization of gating system design for high pressure die casting to reduce air entrapment defects. In 72nd World Foundry Congress, 21-25 May 2016 (pp. 303-304). Nagoya, Japan: The WFO (The World Foundry Organization Ltd).
• [9] Cao, H. et al. (2019). Direct observation of filling process and porosity prediction in high pressure die casting. Materials. 12(7), Article number 1099. DOI: 10.3390/ma12071099.
• [10] Trytek, A. et al.. (2016). The Effect of a Thin-Wall Casting Mould Cavity Filling Conditions on the Casting Surface Quality. Archives of Foundry Engineering. 16(4), 222-226. DOI: 10.1515/afe-2016-0113.
• [11] Otsuka, Y. (2014). Experimental verification and accuracy improvement of gas entrapment and shrinkage porosity simulation in high pressure die casting process+. Materials Transactions. 55(1), 154-160. DOI: 10.2320/matertrans.F-M2013835.
• [12] Majernik, J. et al.. (2019). The influence of the gate geometry on selected process parameters in the high pressure die casting technology. Manufacturing Technology. 19(1), 101-106. DOI: 10.21062/ujep/251.2019/a/1213-2489/mt/ 19/1/101.

Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019)