Wyniki wyszukiwania - BazTech

1

High temperature wettability and reactivity between molten Mg in contact with Ni substrate

Kudyba A., Sobczak N., Turalska P., Bruzda G., Makaya A., Pambaguian L.

Prace Instytutu Odlewnictwa

|

2018

|

Vol. 58, no. 1

47--53

EN

The paper focuses on the experimental investigation of high temperature wetting behaviour of liquid pure Mg during a contact heating on Ni substrate by the sessile drop method. High temperature wettability test was performed by the classical sessile drop method at T = 700°C for t = 300 s, under flowing Ar 99.999% atmosphere, by using the equipment and testing procedures that have been developed by the Foundry Research Institute. In order to suppress effects of heating and cooling histories on wetting and spreading behaviours, Mg/Ni couple was introduced inside a metallic heater already preheated up to the test temperature, while after the wettability test, it was immediately removed to the cold part of the chamber. During the wettability test, images of the couple were recorded by high-resolution high-speed CCD camera. It was observed, that the wetting phenomenon (θ ≤ 90°) takes place immediately after melting of Mg sample. The Mg/Ni system shows a good wetting at T = 700°C after t = 300 s forming the final contact angle of 18°.

PL

Praca prezentuje wyniki badań wysokotemperaturowego oddziaływania ciekłego Mg w kontakcie z podłożem Ni podczas wspólnego nagrzewania badanej pary materiałów. Wysokotemperaturowe badania zwilżalności przeprowadzono klasyczna metodą kropli leżącej w temperaturze T = 700°C i czasie t = 300 s w gazie przepływowym Ar 99,999%. Do badań zastosowano aparaturę i procedury badawcze opracowane w Instytucie Odlewnictwa. W celu eliminacji wpływu historii nagrzewania i chłodzenia na zwilżalność i rozpływność, badany układ Mg/Ni wprowadzono do gorącej części komory badawczej nagrzanej do temperatury badań. Po badaniach zwilżalności badaną parę materiałów natychmiast wprowadzono do zimnej części komory badawczej. Podczas badań zwilżalności stosowano ciągłą rejestrację obrazu badanej pary materiałów za pomocą wysokorozdzielczej kamery cyfrowej CCD. Zaobserwowano, że zjawisko zwilżania (θ ≤ 90°) zachodzi natychmiast po stopieniu próbki czystego Mg. Układ Mg /Ni wykazuje bardzo dobrą zwilżalność w temperaturze T = 700° C po t = 300 s, a końcowa wartość kąta zwilżania wynosi 18°.

2

Napięcie powierzchniowe ciekłych stopów Cu-Fe

Siwiec G.

Rudy i Metale Nieżelazne

|

2010

|

R. 55, nr 12

848-850

PL

W artykule przedstawiono uzyskane metodą kropli leżącej w temperaturach 1473 K oraz 1673 K, wyniki pomiarów napięcia powierzchniowego ciekłych stopów miedzi z żelazem o zawartości 0,01 do 0,05 ułamka molowego Fe. Badania przeprowadzone zostały przy użyciu mikroskopu wysokotemperaturowego sprzężonego z kamerą oraz komputerem wyposażonym w program umożliwiający sterowanie parametrami pracy, rejestrację i analizę obrazu. Przy wyznaczaniu napięcia powierzchniowego wykorzystana została procedura obliczeniowa, polegająca na estymacji metodą najmniejszej sumy kwadratów, parametrów układu równań różniczkowych opisującego kształt leżącej kropli cieczy. Na podstawie przeprowadzonych badań stwierdzono, że wzrost zawartości żelaza w stopach Cu-Fe prowadzi do podwyższenia wartości napięcia powierzchniowego. Wzrostowi temperatury badanych stopów, podobnie jak w przypadku czystych metali oraz zdecydowanej większości układów dwu- i wieloskładnikowych, towarzyszy spadek napięcia powierzchniowego.

EN

In the paper, the results of surface tension measurements at 1473 K and 1673 K with the use of the sessile drop method, concerning liquid copper-iron alloys with 0.01 to 0.05 Fe molar fractions, have been presented. The experiments were conducted using the measuring apparatus PR-37/1600 produced by the Industrial Electronics Institute in Warsaw. It consisted of a high-temperature pipe furnace allowing the observation of a sample placed inside a horizontal reaction chamber (called a high-temperature microscope) and a camera, both coupled with a computer equipped with a program for the device work parameter control as well as for recording and analyzing pictures. The program was used for measurements of appropriate geometric parameters of liquid alloy drops which were necessary for surface tension evaluation. In order to determine the surface tension, a computational procedure based on the least square estimation of the parameters of the differential equation system was used, describing the shape of a sessile drop of liquid using coordinates of points placed along a curve that forms the outer contour of the drop cross-section. The experiments showed that a higher Fe content in Cu-Fe alloys led to the increase in surface tension. A temperature rise of the investigated alloys, similarly to pure metals as well as a great majority of binary and multicomponent systems, is accompanied by the decrease in surface tension.

3

Influence of iron on the surface tension of copper

Oleksiak B., Siwiec G., Blacha A., Lipart J.

Archives of Materials Science and Engineering

|

2010

|

Vol. 44, nr 1

39-42

EN

Purpose: In the paper, the results of surface tension measurements at 1473 K and 1673 K with the use of sessile drop method, concerning liquid copper-iron alloys with 0.01 to 0.05 Fe molar fractions, are presented. The aim of the study was to determine the effects of iron and temperature on the surface tension of copper. Design/methodology/approach: The experiments were conducted with the use of sessile drop method at 1473 K and 1673 K, in an argon atmosphere. For the investigations, a measuring apparatus PR-37/1600, produced by the Industrial Electronics Institute in Warsaw, was used. It consisted of a high-temperature pipe furnace, allowing the observation of a sample placed inside a horizontal reaction chamber (called a high-temperature microscope), and a camera, both coupled with a computer equipped with a program for the device work parameter control as well as for recording and analyzing pictures. The program was used for measurements of appropriate geometric parameters of liquid alloy drops which were necessary for surface tension evaluation. In order to determine the surface tension, a computational procedure, based on the least square estimation of the parameters of the differential equation system, was used, describing the shape of a sessile drop of liquid using coordinates of points placed along a curve that forms the outer contour of the drop cross-section. Findings: The experiments showed that a higher Fe content in Cu-Fe alloys led to the increase in surface tension. A temperature rise of the investigated alloys, similarly for pure metals as well as a great majority of binary and multicomponent systems, is accompanied by the decrease in surface tension. Practical implications: Surface tension has a significant impact on obtaining, refining and casting of metals and alloys. Thus, the knowledge of this parameter may be useful for both a description of phenomena that occur during these processes and their improvement. Originality/value: The presented results may be the first literature data regarding surface tension of Cu-Fe alloys with 0.01 to 0.05 Fe molar fractions.