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Designing of X46Cr13 Steel Heat Treatment in Condition of Casting Mould

Przyszlak Natalia, Piwowarski Grzegorz

Archives of Foundry Engineering

2023

Vol. 23, iss. 2

119--126

The paper presents issues related to the technology of layered castings manufactured in the system: working part made of high-chromium steel X46Cr13 - base part made of gray cast iron with flake graphite, using the mould cavity preparation technology. Considering the high hardenability of the above-mentioned steel grade, the aim of the research was to optimize the casting parameters of gray cast iron in such a way that it would be possible to perform heat treatment of X46Cr13 steel directly in the casting mould. As part of the research, the geometry of the working and base parts of layered castings was selected, and guidelines for mould technology from the point of view of the moulding sand were developed. In order to control the cooling rate, three matrix of the moulding sand were used - quartz sand, chromite sand and silicon carbide, with the same granularity. The thermal conductivity coefficient of sands made on selected matrix, bound with synthetic resin in the ratio of 30:1, was experimentally determined. Then, the bimetal casting process in a given mass was simulated in the MagmaSoft® (ver. 5.4.1). The purpose of the simulation was to determine the maximum virtual temperature Tm in the thermal center of the outer surface of the X46Cr13 steel insert. From the point of view of the research purpose, the insert was expected to heat up to the austenitization temperature, i.e. at least 950°C.

Influence of the Cooling Rate on Damping Characteristics of the ZnAl4Cu1 Alloy

Piwowarski Grzegorz, Gracz Beata

Journal of Casting & Materials Engineering

2022

Vol. 6, no. 3

58--63

The paper presents the results of damping coefficient tests in the ZnAl4Cu1 alloy (ZL5). The damping coefficient has been calculated on the basis of specimen measurements obtained with the use of the signal echo method. The method consists in passing the ultrasonic wave through the tested material. The ultrasonic wave from a transmitting and receiving head passes through a specimen, bounces off its bottom surface and comes back to the measuring head in the form of a signal echo. Difference in the signal strength between the first and the second echo in relation to the distance travelled by the ultrasound wave is a measure of the material’s damping characteristics. The specimens were cast into three molds made of different materials, i.e. green sand, plaster and metal. Thermophysical properties of these materials are different what affecting the rate of heat absorption from the cast. Three series of specimens have been obtained which cooled at different rates. The specimens were then subjected to ultrasound and microscopic tests to assess the alloy structure. The internal alloy structure affects its damping properties to a great extent.

Dobór zasypek egzotermiczno-izolacyjnych dla odlewów ze stopów żelaza

Czech Adam, Czech Bartosz, Banaś Marian, Holtzer Mariusz, Piwowarski Grzegorz, Kasprzyk Magdalena, Łagoda Grzegorz, Różycki Sławomir, Turlej Tymoteusz

Przemysł Chemiczny

2019

T. 98, nr 9

1399--1401

Przygotowano i zbadano 6 zasypek egzotermiczno- izolacyjnych dla odlewów ze stopów żelaza, sporządzonych z wykorzystaniem produktów z mechanicznego przerobu zgarów aluminiowych. Dla zasypek tych oznaczono skład chemiczny, skład ziarnowy, ciepło spalania i straty prażenia. Przeprowadzone próby półprzemysłowe dla odlewów żeliwnych i staliwnych wykazały dużą skuteczność wybranych zasypek.

Six exothermal-insulating powders for Fe alloy castings were prepd. from Al recycling dross and studied for chem. composition, sieve anal., loss on ignition and heat of combustion. The trials conducted under semi-tech. conditions, with the prototype powders revealed their good quality and effectiveness in the metallurgical process, comparable to the currently applied sleeves.