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Influence of plunger motion profile of high pressure die casting on the casting porosity and solidification rate

Żak Katarzyna, Dańko Rafał, Żak Paweł L., Kowalczyk Wojciech

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 5

art. no. e147339

EN

The high pressure die casting (HPDC) is a technique that allows us to produce parts for various sectors of industry. It has a great application in such sectors as automotive, energy, medicine, as the HPDC allows us to produce parts very fast and very cheaply. The HPDC casting quality depends on many parameters. The parameters among others, are cast alloy alloy metallurgy, filling system design, casting technology elements geometry and orientation, as well as, machine operation settings. In the article, different plunger motion schemes of the HPDC machine were taken into account. Analyses lead to learning about plunger motion influence on the casting porosity and solidification process run. Numerical experiments were run with the use of MAGMASoft® simulation software. Experiments were performed for industrial casting of water pump for automotive. Main parameter taken into account was maximal velocity of the plunger in the second phase. The analysis covered porosity distribution, feeding time through the gate, temperature field during whole process, solidification time. Cooling curves of the casting in chosen points were also analysed. Obtained results allow us to formulate conclusions that connect plunger motion scheme, gate solidification time and the casting wall thickness on the solidification rate and porosity of the casting.

2

Investigations of the Influence of the Zone of Chills on the Casting Made of AlSi7Mg Alloy with Various Wall Thicknesses

Piękoś M., Zych J.

Archives of Foundry Engineering

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2019

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iss. 1

127--132

EN

The influence of the chill on the AlSi7Mg alloy properties after the heat treatment T6, was realised in the system of the horizontally cast plate of dimensions 160x240 mm and thickness of 10 and 15 m. The cooling course in individual casting zones was recorded, which allowed to determine the solidification rate. Castings were subjected to the heat treatment T6 process. Several properties of the alloy such as: hardness BHN, density, tensile strength UTS, elongation %E were determined. The microstructure images were presented and the structural SDAS parameter determined. The performed investigations as well as the analysis of the results allowed to determine the influence zone of the chill. The research shows that there is a certain dependence between the thickness of the casting wall and the influence zone of the chill, being not less than 2g, where g is the casting wall thickness. The next aim of successive investigations will be finding the confirmation that there is the dependence between the casting wall thickness and the influence zone of the chill for other thicknesses of walls. We would like to prove that this principle is of a universal character.

3

A study of interfacial heat transfer and its effect on quenching when hot stamping AA7075

Xiao W., Wang B, Zheng K., Zhou J., Lin J.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 3

723--730

EN

The aim of this research was to investigate the effects of contact pressure and lubrication on the interfacial heat transfer coefficient (IHTC) between AA7075 sheet and H13 tool steel and the in-die quenching performance in hot stamping. Firstly, a series of designed in-die quenching experiments were performed using different contact pressures, 0.05–30 MPa and lubrication conditions to determine the IHTC values using an efficient methodology. Secondly, temperature evolution of the tools and blank during the in-die quenching was investigated. Mechanical properties of material in-die quenched under different process conditions, were measured to determine their relation to quench conditions. The results have shown that IHTC values increased with increasing contact pressure and use of lubricant. A strength level of T6 condition could be obtained using a contact pressure greater than 5 MPa in the lubricated condition.

4

Influence of molding sand on the number of grains graphite and on the rate of thin ferrite in pieces in a nodular iron ferritic matrix

Khatemi B.

Archives of Foundry Engineering

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2010

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Vol. 10, iss. 3 spec.

303--309

EN

The nodular cast irons are characterized by high mechanical properties compared to cast iron with lamellar graphite or vermicular graphite. The ductile iron has already been the subject of many studies especially since the literature is rich on them, and sources of information are different. The fact is that the mechanical properties of nodular cast iron (FGS) depend on the number of graphite grains, their roundness, the solidification rate and nature of the matrix [3]. Many studies of nodular cast irons showed that the more spherical particles of graphite, the higher the mechanical properties are high. In gray cast irons, the graphite spheroids have anticracking and give the ductile iron ductility. Note in this connection that the higher the number of graphite grains, the higher the ductile iron has better mechanical properties. In cast iron, the nature of the matrix is depending on several parameters including the cooling rate of molten metal, the thickness, shape and dimensions of parts. The faster cooling is slow over rate of ferrite is important [3, 4]. In this paper, we tested three types of sand casting: sand –based sodium silicate, furan resin and green sand on samples spherical graphite cast iron of different thickness. The objective in this article is to determine the number of grains of graphite and ferrite for each type of sand casting under the same experimental conditions including the cooling rate and chemical composition of the liquid metal.

5

Analiza przebiegu procesu schładzania potraw w schładzarce szokowej

Grzesińska W., Sieradzka A.

Inżynieria Rolnicza

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2005

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R. 9, nr 9

125--132

PL

Celem badań było przeprowadzenie analizy przebiegu procesu szokowego schładzania wybranej potrawy w dwóch typach szybkoschładzarek. Badaniu poddano rozkład temperatury w schładzanej potrawie oraz zweryfikowano założenia teoretyczne dla przebiegu procesu schładzania. Materiałem badawczym były mrożone pierogi z serem, które po obróbce termicznej w piecu konwekcyjno – parowym poddano szokowemu schłodzeniu. Podczas procesu mierzono rozkład temperatury w pierogach oraz tempo obniżania się temperatury powietrza w komorze szybkoschładzarki. W oparciu o uzyskane wyniki w jednym z badanych urządzeń stwierdzono nierównomierność przebiegu procesu schładzania pierogów oraz niezgodność przebiegu tego procesu z teoretycznymi założeniami dla szokowego schładzania potraw o niskiej gęstości.

EN

The main goal of researches was analysis performance of blast chilling of selected dish process in two types of blast chillers. Analyzed was temperature resolution in chilled dish and verified was theoretical foundations for chilling process. As an analyzed substance used frozen dumplings filled with cheese, which after thermal processing in combi oven were blast chilled. During this process was measured temperature resolution in dumplings and rate of air temperature reducing in blast chiller chamber. Based on received results in one of analyzed devices dumplings chilling process irregularity and incompatibility of this process with theoretical foundations for blast chilling of low density dishes was ascertained.