Wyniki wyszukiwania - BazTech

1

Cykliczny proces odkształcania stopu CuFe2 - analiza struktury i właściwości

Brzezińska Agata, Rodak Kinga, Sobota Joanna

Rudy i Metale Nieżelazne Recykling

|

2019

|

R. 64, nr 4

12--16

PL

W artykule przedstawiono wstępne wyniki badań stopu CuFe2 poddanego cyklicznemu odkształcaniu przy wykorzystaniu metody KOBO. Procesowi odkształcania poddano materiał bezpośrednio po odlaniu oraz po przesycaniu w temperaturze 1000°C w czasie 3 h. Proces wyciskania prowadzono przy stałych parametrach procesu (kąt obrotu matrycy 8°, częstość obrotu matrycy 4-5 Hz). Badania strukturalne zostały przeprowadzone z wykorzystaniem mikroskopu świetlnego i skaningowego mikroskopu elektronowego. Poprzez pomiary przewodności właściwej oraz wyniki statycznej próby rozciągania i pomiary twardości HV0,2 oceniono właściwości mechaniczne i fizyczne. Na podstawie przeprowadzonych badań stwierdzono, że niezależnie od stanu wyjściowego materiału zastosowanie wyciskania metodą KOBO umożliwia rozdrobnienie struktury stopu CuFe2 do poziomu ultradrobnoziarnistego.

EN

In this paper have been presented the preliminary results of CuFe2 alloy investigations during cyclic deformation by using KOBO methods. Material has been processed after casting and quenching processes. The quenching process has been performed at 1000°C during 3 h. KOBO process was carried out at constant technological parameters as: torsion angle 8°, torsion frequency 4-5 Hz. Structural investigations were performed by using light microscopy and scaning electron microscopy. By measurement of termal conducitvity, tests of strenght and hardness measurements the received mechanical and phisical properties were determined. The obtained result showed, that independently of initial state of material it is possible to obtain ultrafine grained structure by using KOBO method.

2

Experimental studies and finite element simulation of ultrasonic welding of Cu alloy

Mohan-Raj N., Kumaraswamidhas L. A., Arungalai-Vendan S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2016

|

Vol. 64, nr 3

535--546

EN

This research study aims to investigate the mechanical and metallographical aspects of ultrasonic welding of Cu-Cu wires. Experimental trials have been conducted and observations have been recorded as a database that collates parametric, quality and strength aspects of various weldments. Destructive testing and metallurgical characterizations have been carried out to examine the strength and integrity of the weldment. The key focus of this research attempt is laid on determining and evaluating the factors that governs the strength of the weldment. Metallurgical characterizations reveal vital information on the weld integrity and the extent of grain distribution. Further, FEM is employed to understand the deformation and thermal aspects involved in Cu-Cu welding using ultrasonics. The numerical model may provide an insight into the thermal phenomenon governing the joining process and subsequently estimation of the impact. Response surface methodology is employed to identify the parametric interdependencies and subsequently determine the optimized range.

3

Badania odporności korozyjnej bezołowiowych mosiądzów z dodatkami cyny i niklu

Kondracki M.

Ochrona przed Korozją

|

2012

|

nr 5

242-245

PL

W artykule przedstawiono wyniki badań odporności korozyjnej bezołowiowych mosiądzów ze zmiennym udziałem dodatków cyny i niklu. Głównym celem było określenie jakościowe procesu korozji w środowisku sprzyjającemu odcynkowaniu. Uzyskane wyniki umożliwiły określenie szybkości procesu korozji przy zmiennym składzie chemicznym. Sformułowano wstępne wnioski na temat zależności między składem chemicznym, strukturą stopu a szybkością korozji badanych stopów.

EN

In this paper the results of corrosion tests for non-leaded brasses with variable content of tin and nickel were presented. The main aim was the qualitative description of the corrosion process in the dezincification favourable environment. The obtained results enabled the corrosion rate evaluation at different chemical composition of the alloy. Initial conclusions has been formulated on the relations between chemical composition, structure and the corrosion rate for investigated alloys.

4

Special non-leaded brasses for permanent mould casting

Kondracki M., Szajnar J.

Journal of Achievements in Materials and Manufacturing Engineering

|

2007

|

Vol. 25, nr 2

17-23

EN

Purpose: Leaded brasses are most commonly used Cu alloys, especially for home fixture. High toxicity of lead to human caused tendency to eliminate this additions from these alloys. In this work a discussion of solutions to this problem is shown and possibilities of leaded brasses replacement with multi-component non-leaded brasses. Design/methodology/approach: In this work general properties of multi - component brasses are investigated (mechanical, technological and operating properties) as well as its structure and their correlation with chemical composition. Some interactions of additions are shown with physical and mathematical model of its influence on properties. Findings: It was found that in a complex of additions (closed system) the interactions can be described by physical model and mathematical equations showing properties in function of chemical composition can be used to optimize chemical composition for engineering alloys with known properties. Research limitations/implications: However introducing new elements to the system (chemical composition) will disturb the created models (physical and mathematical). It must be said that for investigated alloys optimal properties can be ensured using presented models. Practical implications: Presented approach enables optimization of alloy properties for particular application. Properties can be introduced to the mathematical model which with use of optimization methods will return needed chemical composition. Originality/value: Alloys engineered with use of presented approach have properties close to leaded brass with low increase in total production costs.

5

Possibilities for leaded brass replacement with multi-component brass

Kondracki M., Szajnar J.

Archives of Foundry Engineering

|

2007

|

Vol. 7, iss. 2

57-64

EN

Leaded brasses are most commonly used Cu alloys, especially for home fixture. High toxicity of lead to human caused tendency to eliminate this additions from these alloys. In this work a discussion of solutions to this problem is shown and possibilities of leaded brasses replacement with multi – component non – leaded brasses. In this work general properties of multi – component brasses are investigated (mechanical, technological and operating properties) as well as its structure and their correlation with chemical composition. Some interactions of additions are shown with physical and mathematical model of its influence on properties. It was found that in a complex of additions (closed system) the interactions can be described by physical model and mathematical equations showing properties in function of chemical composition can be used to optimize chemical composition for engineering alloys with known properties. However, introducing new elements to the system (chemical composition) will disturb the created models (physical and mathematical). It must be said that for investigated alloys optimal properties can be ensured using presented models. Presented approach enables optimization of alloy properties for particular application. Properties can be introduced to the mathematical model which with use of optimization methods will return needed chemical composition. Alloys engineered with use of presented approach have properties close to leaded brass with low increase in total production costs.

6

Wzajemne oddziaływania pierwiastków w kształtowaniu własności odlewniczych stopów miedzi z cynkiem stosowanych na elementy armatury

Kondracki M., Gawroński J., Szajnar J.

Rudy i Metale Nieżelazne

|

2005

|

R. 50, nr 5

249-252

PL

Niniejszy artykuł pokazuje wybrane wyniki uzyskane w badaniach nad zależnościami pomiędzy składem chemicznym a pojawiającymi się w mikrostrukturze stopów miedzi z cynkiem wydzieleń międzymetalicznych. Wydzielenia te, zwane też twardymi, oddziałują silnie na własności stopu, przede wszystkim na jego plastyczność, twardość i skrawalność. Autorzy wskazują najbardziej aktywne pierwiastki tworzące owe fazy oraz ukazują pewne wzajemne oddziaływania pomiędzy dodatkami stopowymi. Ponadto, podają wybrane wyniki uzyskane przy pomocy analizy termicznej i derywacyjnej. Wskazano zależności położenia punktów charakterystycznych krzywych ATD od ilości i rodzaju pojawiających się składników osnowy.

EN

This article shows some of the results obtained in the studies on relations between chemical composition and the hard inclusions occurrence in fixture brass structure. These inclusions have strong influence on alloy properties such as plasticity, hardness and machinability. Authors indicate the most active elements in creating such phases and present some interactions between the alloy components. Additionally a selection of results obtained in thermal and derivative analysis are presented. Possible relations between characteristic points of TDA curves and the hard inclusions quantity were showed.