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Optimization on friction and wear behaviour of Al-Si alloy reinforced with B4C particles by Powder Metallurgy using Taguchi design

Jeya Raj R., Lenin Anselm W. A., Jinnah Sheik Mohamed M., Christopher Ezhil Singh S., John T. D., Rajeev D., Glan Devadhas G., Jaya Christyan K. G., Malkiya Rasalin Prince R., Jeen Robert R. B.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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Vol. 68, nr 6

1393--1402

EN

This research paper discusses the friction and wear behaviour of Al-12Si alloy reinforced with B4C prepared through Powder Metallurgy (P/M) method by varying the weight percentage of reinforcement (x = 2, 4, 6, 8, and 10) content. The samples were prepared by using die and punch assembly and the lubricant used to eject the sample from the die was molybdenum disulfide. The compaction was done by using a compression testing machine by applying a pressure of 800 MPa. The dry sliding friction and wear behaviour of the sample was conducted on a Pin-on-Disc machine and the experimental values of friction and wear were calibrated. The Taguchi design experiment was done by applying an L25 orthogonal array for 3 factors at 5 levels for the response parameter Coefficient of Friction (CoF) and wear loss. The SEM images show the shape, size and EDX confirm the existence of Al, Si, B4C particles in the composites. Analysis of Variance (ANOVA) for CoF of S/N ratio, shows that the reinforcement having 34.92% influence towards the S/N ratio of CoF, ANOVA for wear loss of S/N ratio shows that the sliding distance having 46.76% influence towards the S/N ratio of wear loss, when compared to that of the other two input parameters. The interaction line plot and the 2Dsurface plot for CoF and wear loss show that the increase in B4C content decreases the wear loss and CoF. The worn surface shows that the B4C addition will increase the wear resistance.

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The Fluidity of Al-Si Alloy: Computer Simulation of the Influence of Temperature, Composition, and Pouring Speed

Futáš P., Petrík J., Pribulová A., Blaško P., Palfy P.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1799--1804

EN

The purpose of this study is to identify relationships between the values of the fluidity obtained by computer simulation and by an experimental test in the horizontal three-channel mould designed in accordance with the Measurement Systems Analysis. Al-Si alloy was a model material. The factors affecting the fluidity varied in following ranges: Si content 5 wt.% – 12 wt.%, Fe content 0.15 wt.% – 0.3 wt. %, the pouring temperature 605°C-830°C, and the pouring speed 100 g · s-1 – 400 g · s-1. The software NovaFlow&Solid was used for simulations. The statistically significant difference between the value of fluidity calculated by the equation and obtained by experiment was not found. This design simplifies the calculation of the capability of the measurement process of the fluidity with full replacement of experiments by calculation, using regression equation.

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Wpływ kształtu formy na skurcz liniowy tworzonego stopu EN AC-48000

Kujawa K.

Przegląd Mechaniczny

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2015

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nr 2

29--32

PL

W pracy przedstawiono wyniki badań nad zjawiskiem skurczu liniowego krzepnącego i stygnącego odlewu siluminowego. W prowadzonych badaniach zastosowano formy metalowe odwzorowujące odlew pionowego pręta testowego o przekroju okrągłym (stałym lub zmiennym). Zastosowanie dwóch wariantów form zagwarantowało uzyskanie porównywalnych warunków stygnięcia przy uzyskaniu warunków skurczu ideowo swobodnego (forma o zbieżności 1:100, niedzielona) oraz skurczu hamowanego (forma walcowa, dzielona) jedynie na powierzchni odlew-forma. Na podstawie rejestrowanych zmian temperatury odlewu oraz zmian wymiaru osiowego krzepnącego odlewu i formy testowej określono kinetykę skurczu liniowego oraz zmian współczynnika liniowej rozszerzalności cieplnej w funkcji temperatury Przedstawiono wyniki badania skurczu liniowego uzyskane w formie ze zbieżnością oraz bez niej (walcowej).

EN

The paper presents results of research on the phenomenon of linear shrinkage and cooling silumin. In this study using a metal mold test mapping casting circular cross-section vertical rod (fixed or variable). Use of two variant forms of guarantees comparable cooling conditions in obtaining spasm of ideological freedom (form convergence of 1:100, unshared) and inhibits the contractions (as a cylindrical joint) only the surface of the mold. Based on the recorded temperature changes and changes in the casting of the axial dimension of the casting mold and solidification of the test set, certain intensity and the change of the linear shrinkage coefficient of linear expansion of heat as a function of temperature. Shows the result of research in the form of linear contraction and convergence without it (cylindrical).

4

Machinability of modified AlSi7Mg0,3 alloy

Naprstkova N., Cais J.

Production Engineering Archives

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2014

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Vol. 3, No. 2

10--13

EN

Al Alloys have an important position in the industry, mainly in the automotive and aerospace industries. One important group is silumins (Al-Si alloys). Al-Si alloys are the leading casting alloys based on aluminum. Machining of aluminum alloys is currently frequently used and it is an important area of production. This paper deals with an experiment that was conducted at the Faculty of Production Technology and Management, University of Jan Evangelista Purkyně in Ústí nad Labem, where alloy AlSi7Mg0,3 was experimented upon. Samples were made for processing from the master alloy AlSi7Mg0,3, subsequently unmodified and modified of Sr, Ca and Sb. This paper describes the evaluation of hardness, chip and tool wear in terms of how modification by Sr, Ca and Sb may affect analytical values.

5

Statistical control of machined high pressure die casting geometry by using of JM-SPC software

Mutwil J.

Archives of Foundry Engineering

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2009

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Vol. 9, iss. 4

141-148

EN

Usefulness of newest version of the JM-SPC computer program for a statistical analysis of production processes was examined. An analysis subject were results of measurements of 16 geometrical features of an Al-Si high-pressure die casting systematically controlled after machining on a coordinate-measuring machine. For analysis two criterion have been used: 1) Xave control chart and 2) a performance indicator of processes expressed by two commonly used indices: potential process capability index (Cp) and process capability index (Cpk).

6

Examples of thermal derivative gradient analysis (TDGA) application

Cholewa M., Suchoń J., Kondracki M.

Archives of Foundry Engineering

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2009

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Vol. 9, iss. 4

23-30

EN

The study presents the possibility of TDGA method based on multipoint measurement of temperature during crystallization of two test castings poured from different temperature. Sample castings have conical shape. Temperature measurement is carried out in six cone cross-sections between the heat axis and the surface of the mould cavity. The multichannel recording device allows describing the thermal derivative after time and direction. Presented examples of the assessment of kinetics of crystallization for alloys: AlSi11, CuSn8 and GJL 200 cast iron. Based on quantitative analysis of the microstructure (DAS, fig. 1 and tab.1) examples of relations were prepared, describing the mechanical and structural properties in function of crystallization kinetics parameters - DAS = f(vchł) DAS = f(\delta(dT/dt)/dt) HV = f(Gy) Rm = f(\delta(dT/dt)/dt) as shown in fig. 2 and 4. The evaluation of crystallization process was also conducted for AlSi11 skeleton castings. Pointed out was the universality of the method with respect to the mathematical interpretation of the results and its limitations due to data registration extracted from multiple thermocouples. Based on the conducted studies, the method can be applied in the industry as well as in the experimental practice.

7

Model krystalizacji odlewu warstwowego poprzez powłokę alfinowaną

Pietrowski S., Szymczak T.

Inżynieria Materiałowa

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2006

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Vol. 27, nr 5

1178-1183

PL

W pracy przedstawiono wyniki badań nanoszenia zanurzeniowo w kąpieli Al-Si warstwy alfinowanej na stali i żeliwie, oraz krystalizację poprzez nią odlewu warstwowego. Podano budowę warstwy alfinowanej oraz połączenia odlewu warstwowego. Omówiono wybrane czynniki technologiczne wpływające na grubość warstwy. Przedstawiono prawdopodobny mechanizm krystalizacji warstwy alfinowanej i odlewu warstwowego. Wyniki badań zweryfikowano w warunkach produkcyjnych.

EN

In these paper results of immersing creation in Al-Si bath the alphinizing coat on steel and cast iron, and a crystallization of a layered cast through it have been presented. A structure of alphinizing coat and joints inside the layered cast have been presented. The influence of selected technological elements on the coat thickness has been discussed. The probably crystallization mechanism of alphinizing coat and layered cast has been presented. The results were verified in production conditions.

8

Numeryczna symulacja tiksotropowego wypełniania formy stopem AlSi.

Sołek K., Wajda W., Pietrzyk M., Mitura Z., Białobrzeski A.

Rudy i Metale Nieżelazne

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2001

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R. 46, nr 11

579-583

PL

Priorytetowym zadaniem niniejszej pracy jest opis poprawnego mechanizmu wypełniania formy oraz odpowiedni dobór reologii półciekłego metalu. Przeprowadzono analizę proponowanych w literaturze naukowej modeli ciał odkształconych w warunkach tiksotropowych. W dalszej kolejności przeprowadzono pilotażowe symulacje formowania skomplikowanego kształtu programem Forge2 (R). W symulacji założono model ciała lepko-plastycznego opisanego równaniem Nortona-Hoffa. Wybrane wyniki przedstawiono w formie pól prędkości odkształcenia i naprężeń. Podjęto zatem próbę weryfikacji uzyskanych wyników symulacji z wynikami doświadczalnymi.

EN

The objective of this work is description of the mechanism of die filling and verification of the selection of rheology of metal in semi-solid state. The most important theoretical models taken from literature are discussed. Next the preliminary simulation of net-shape forming is presented. The software Forge2 (R) with the viscoplastic Norton-Hoff constitutive model was used in the simulation. The results of computing are shown in the form of velocity and strain fields. The comparison of the simulation and experiment allowed validation of the model.

9

Stront jako modyfikator stopów AlSi i AlSiCu.

Łatkowski A., Bronicki M., Gryziecki J.

Rudy i Metale Nieżelazne

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1999

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R. 44, nr 3

101-107

PL

Opierając się na analizie zmian mikrostruktury określono optymalne ilości strontu zapewniające efekt modyfikacji w stopach AK7, AK9, AK11, AK52 i AK 104. Zbadano również trwałość modyfikatora poprzez kolejne przetopy odlewów. Przeprowadzono badania wpływu ilości modyfikatora na udarność stopów.

EN

The optimum strontium amount for good modification of AK7, AK9, AK11, AK52, AK104 alloys was determined on the base of the analysis of microstructural changes. The stability of the modifier was investigated on the way of succesive remelting of billets. The influence of amount of modifier on the impact strength of the alloys was established.