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Recent studies on particulate reinforced AZ91 magnesium composites fabricated by stir casting - a review

Matta Anil Kumar, Koka Naga Sai Suman, Devarakonda Sameer Kumar

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 2

115--126

EN

Magnesium Metal Matrix Composites (Mg MMC) have been the focus of consideration by many researchers for the past few years. Many applications of Mg MMCs were evolved in less span of time in the automotive and aerospace sector to capture the benefit of high strength to weight ratio along with improved corrosion resistance. However, the performance of these materials in critical conditions is significantly influenced by several factors including the fabrication methods used for processing the composites. Most of the papers addressed all the manufacturing strategies of Mg MMC but no paper was recognized as a dedicated source for magnesium composites prepared through STIR casting process. Since STIR casting is the least expensive and most common process in the preparation of composites, this paper reviews particulate based Mg MMCs fabricated with STIR casting technology. AZ91 series alloys are considered as the matrix material while the effect of different particle reinforcements, sizes, weight fractions on mechanical and tribological responses are elaborated in support with micro structural examinations. Technical difficulties and latest innovations happened during the last decade in making Mg MMCs as high performance material are also presented.

2

Tribological behavior of AA7050-ZrSiO4 composites synthesized by stir casting technique

Sakthivelu S., Meignanamoorthy M., Ravichandran M., Sethusundaram P. P.

Mechanics and Mechanical Engineering

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2019

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Vol. 23, nr 1

198--201

EN

This research made an attempt to synthesize aluminum metal matrix composites through stir casting technique. The matrix material chosen in this study was AA7050 and the reinforcement material was ZrSiO4. The composites AA7050, AA7050-10%ZrSiO4, and AA7050-15%ZrSiO4 were used. The wear behavior of the aluminium matrix composites was investigated by using pin-on-disc tribometer. The advanced material has substantial development in tribological behavior when the reinforcement percentage is increased. From the experimental results, it was confirmed that sliding distance of 1200 m, applied load of 3 N and sliding speed of 2 m/s result in minimum wear loss and coefficient of friction, while adding 10%ZrSiO4 to the AA7050.

3

Experimental evaluation of Al-Zn-Al2O3 composite on piston analysis by CAE tools

Krishnan B. Radha, Ramesh M.

Mechanics and Mechanical Engineering

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2019

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Vol. 23, nr 1

212--217

EN

Today’s automotive designers and material specialists regard lighter vehicles for less fuel consumption (economy and ecology) and higher safety to passengers. Metal matrix composites have been a large area of interest. Aluminium composite is potentially applied in automotive and aerospace industries, because it has a superior strength to weight ratio and is a light weight metal with high temperature resistance. Composites containing hard oxides and ceramics (such as alumina) are preferred for high wear resistance along with increased hardness. In thiswork, alumina and zinc are reinforced in Al-LM25 alloy through stir casting process, where alumina is varied 6% and 12% in Al-5%Zn. Various mechanical analyses were conducted and the effect of wear with different percentage of alumina reinforcement was studied. The resulting properties are imported in a piston, modelled using solidworks, and analysed in ANSYS work bench. Imparting this new material for pistons could introduce deep design and improvements in engine operation of a vehicle.

4

A review on multiple responses process parameters optimization of turning Al-TiCp metal matrix composites

Naresh P., Hussain S. A., Prasad B. D.

Journal of Achievements in Materials and Manufacturing Engineering

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2017

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Vol. 80, nr 1

32--40

EN

Purpose: In this paper the Metal Matrix Composites of AL 7068 and TiC with different proportions of (2%, 4%, 6%, 8%, and 10%) by using stir casting process, mechanical properties and machining responses are investigating. Design/methodology/approach: The samples are fabricated using stir casting, machining of turning the samples by using Kilster Tool Lathe Dynamometer machining responses were identifying. Findings: In this research to find mechanical characterizations like flexural strength, Wear ratio, impact strength, hardness, microstructure and also machining responses like surface roughness, cutting force, cutting power, tool wear ratio and can be optimized by multiple responses. Research limitations/implications: This paper research about the mechanical characterization and machining of AL-7068&TiC that focuses on machining responses and microstructures. Originality/value: By surveying the research articles the gap will be identified in AA-7068&TiC depended on machining responses and mechanical characterizations.

5

The influence of remelting parameters on Mg alloy/glassy carbon suspension stability

Olszówka-Myalska A.

Composites Theory and Practice

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2014

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R. 14, nr 2

96--100

EN

The homogenous distribution of reinforcing phases in a liquid metal matrix determines the final properties of composite elements fabricated by the casting of a suspension. Ensuring not only a proper temperature and stirring conditions during suspension preparation, but also a relatively short time between the end of mixing and the start of suspension pouring into moulds is critical. In the article, investigations focused on the migration of glassy carbon particles (GCp) in two melted magnesium alloys, Mg3Al and Mg2ZnZrRE, were presented. The composites previously obtained by the stir casting method were remelted at the temperatures of 610, 640, 690 and 730°C (time 30, 60 and 90 min) and finally cooled at a temperature of 20°C. The particles segregation on the macro scale was analyzed on a longitudinal section of the obtained samples. It was revealed that both types of suspensions were stable at 610 and 640°C but at 690 and 730°C, a loss of stability was observed. In spite of the slightly less density of the glassy carbon than the applied magnesium alloys, the type of segregation was different and depended on the alloy chemical composition. In the suspension of Mg3Al-GCp, particle migration to the crucible top was observed only, while in the Mg2ZnZrRE-GCp suspension, two zones with a high particle concentration were formed, separated by a zone of pure metal.

PL

W procesach odlewania kompozytów z zawiesin jednorodność rozmieszczenia fazy zbrojącej w metalowej osnowie decyduje o powtarzalności właściwości wytwarzanych wyrobów. Wymusza to zapewnienie w procesie technologicznym nie tylko odpowiedniej temperatury suspensji i warunków jej mieszania, ale również kontroli czasu pomiędzy zaprzestaniem mieszania a odlaniem wyrobu. W artykule przedstawiono wyniki badań segregacji cząstek węgla szklistego(GCp) w dwóch stopach magnezu Mg3Al i Mg2ZnZrRE. Eksperyment przeprowadzony w warunkach laboratoryjnych obejmował przetop kompozytów uzyskanych wcześniej w warunkach przemysłowych metodą mechanicznego mieszania komponentów i odlewania grawitacyjnego suspensji do form stalowych. Próbki wygrzewano w temperaturze 610, 640, 690 i 730°C w czasie 30, 60 i 90 minut i schłodzono w temperaturze 20°C. Analizowano makrostrukturę przekrojów wzdłużnych pod względem segregacji cząstek. Wykazano stabilność obu suspensji w temperaturze 610 i 640°C oraz jej utratę w temperaturze 690 i 730°C. Charakter segregacji cząstek był różny i zależał od składu chemicznego stopu, pomimo tego, że w obu typach suspensji gęstość cząstek była nieznacznie mniejsza od gęstości stopów. W suspensji Mg3Al-GCp cząstki migrowały do góry tygla, a w suspensji Mg2ZnZrRE-GCp utworzyły dwie strefy u góry i na dole tygla, które rozdzielone były strefą metalu bez cząstek.

6

Technologiczne uwarunkowania stabilności zawiesiny stop magnezu-cząstki węgla szklistego

Olszówka-Myalska A., Myalski J., Hetmańczyk M., Kiełbus A.

Rudy i Metale Nieżelazne

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2013

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R. 58, nr 12

835--839

PL

Przedstawiono wpływ wybranych czynników technologicznych na wytwarzanie i stabilność suspensji ze stopu magnezu Mg-Zn-Zr-RE i cząstek węgla szklistego, którą otrzymano w piecu przemysłowym metodą mechanicznego mieszania. Analizowano wpływ geometrii zastosowanego mieszadła i innych parametrów procesu na przebieg wprowadzania cząstek do ciekłego metalu. Scharakteryzowano warunki występowania segregacji cząstek w suspensji.

EN

Some technological aspects of the magnesium alloy (Mg-Zn-Zr-RE) with glassy carbon particles (GCp) suspension manufacturing and stability were presented. The suspension was obtained by the mechanical stirring method in an industrial furnace (charge mass ~35kg). Three different stirrers manufactured of St3S steel and coated with BN protecting coating were applied in experiments. An influence of the stirrer geometry and the other technological parameters on the effectiveness of particles input into molten alloy was presented. Conditions of the particles segregation in a suspension during and after mixing were described. It was observed at the top part of a melting top. Macrostructure examinations of Mg-Zn-Zr-RE/GCp composite remelted at different time (30-90 minutes) and then crystallized shown that the segregation processes are more complicated that can be expected as a result of higher alloy density than of the particles. Three zones were formed as an effect of particles segregation, two zones with a high particles concentration were separated by a zone of metal with a minor particles amount. An additional segregation of the particles at the ingot bottom can be combined with the segregation of Zr, characteristic for the magnesium alloys with Zr.