Effect of modified drill point geometry on drilling quality characteristics of metal matrix composite (MMCs)

Abstract In this paper it is stated, that a set of quality features of metal matrix composite castings differs from the same set for castings of classic materials, although some features are common for both of these material groups. These features (pertaining to a set of quality characteristics of composite castings) have been named as specific, they have not been determined yet and a description of material quality should be performed (according to the qualitology) on a principle of description of quality characteristics of this product. Therefore, this set of features has been determined. It was proposed to add the following characteristics to the set of specific features of composite castings quality: matrix material, reinforcement material, binding between components and porosity of the composite casting. In this set a sub-set of quality characteristics of composite castings was also determined.

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Effect of Material and Technological Conditions on Quality of Metal Matrix Composite Castings

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.197.180 ◽

2013 ◽

Vol 197 ◽

pp. 180-185 ◽

Cited By ~ 1

Author(s):

Katarzyna Gawdzińska ◽

Dorota Nagolska ◽

Leszek Wojnar

Keyword(s):

Metal Matrix Composite ◽

Human Impact ◽

Technological Process ◽

Matrix Composite ◽

Metal Matrix ◽

Quality Characteristics ◽

Metal Composite ◽

Individual Quality ◽

Ishikawa Diagram

The paper presents a proof, which has been made by analyzing technological process of tested materials, that a set of quality characteristics of metal composite castings has to be different from the set of quality characteristics of castings produced out of traditional materials. However, some characteristics are similar for both material groups. These characteristics (pertaining to a set of quality characteristics of composite castings) that have been named as specific, have not been determined before. The set of characteristics has been determined on the basis of material and technological conditions as well as on methodology of diagnosing the castings quality. Basing on the Ishikawa diagram, weights of individual quality characteristics have been set along with values for particular material and technological causal groups, i.e. management, human impact, methods of manufacturing and material of composite castings and manufacturing workstation.

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TEM examination of 2014-SiC metal matrix composite

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105692 ◽

1988 ◽

Vol 46 ◽

pp. 726-727

Author(s):

M. G. Burke ◽

M. N. Gungor ◽

P. K. Liaw

Keyword(s):

Metal Matrix Composite ◽

Metal Matrix Composites ◽

Matrix Composite ◽

Metal Matrix ◽

Tensile Deformation ◽

Microstructural Characterization ◽

Thin Foil ◽

Matrix Alloy ◽

Matrix Composites ◽

Ion Milling

Aluminum-based metal matrix composites offer unique combinations of high specific strength and high stiffness. The improvement in strength and stiffness is related to the particulate reinforcement and the particular matrix alloy chosen. In this way, the metal matrix composite can be tailored for specific materials applications. The microstructural characterization of metal matrix composites is thus important in the development of these materials. In this study, the structure of a p/m 2014-SiC particulate metal matrix composite has been examined after extrusion and tensile deformation.Thin-foil specimens of the 2014-20 vol.% SiCp metal matrix composite were prepared by dimpling to approximately 35 μm prior to ion-milling using a Gatan Dual Ion Mill equipped with a cold stage. These samples were then examined in a Philips 400T TEM/STEM operated at 120 kV. Two material conditions were evaluated: after extrusion (80:1); and after tensile deformation at 250°C.

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An appraisal of characteristic mechanical properties and microstructure of friction stir welding for Aluminium 6061 alloy – Silicon Carbide (SiCp) metal matrix composite

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.13.4.2019.07.0463 ◽

2019 ◽

Vol 13 (4) ◽

pp. 5804-5817

Author(s):

Ibrahim Sabry

Keyword(s):

Tensile Strength ◽

Ultimate Tensile Strength ◽

Metal Matrix Composite ◽

Matrix Composite ◽

Metal Matrix ◽

Welded Joint ◽

Rotation Speed ◽

Fusion Welding ◽

Friction Stir ◽

Al 6061

It is expected that the demand for Metal Matrix Composite (MMCs) will increase in these applications in the aerospace and automotive industries sectors, strengthened AMC has different advantages over monolithic aluminium alloy as it has characteristics between matrix metal and reinforcement particles. However, adequate joining technique, which is important for structural materials, has not been established for (MMCs) yet. Conventional fusion welding is difficult because of the irregular redistribution or reinforcement particles. Also, the reaction between reinforcement particles and aluminium matrix as weld defects such as porosity in the fusion zone make fusion welding more difficult. The aim of this work was to show friction stir welding (FSW) feasibility for entering Al 6061/5 to Al 6061/18 wt. % SiCp composites has been produced by using stir casting technique. SiCp is added as reinforcement in to Aluminium alloy (Al 6061) for preparing metal matrix composite. This method is less expensive and very effective. Different rotational speeds,1000 and 1800 rpm and traverse speed 10 mm \ min was examined. Specimen composite plates having thick 10 mm were FS welded successfully. A high-speed steel (HSS) cylindrical instrument with conical pin form was used for FSW. The outcome revealed that the ultimate tensile strength of the welded joint (Al 6061/18 wt. %) was 195 MPa at rotation speed 1800 rpm, the outcome revealed that the ultimate tensile strength of the welded joint (Al 6061/18 wt.%) was 165 MPa at rotation speed 1000 rpm, that was very near to the composite matrix as-cast strength. The research of microstructure showed the reason for increased joint strength and microhardness. The microstructural study showed the reason (4 %) for higher joint strength and microhardness. due to Significant of SiCp close to the boundary of the dynamically recrystallized and thermo mechanically affected zone (TMAZ) was observed through rotation speed 1800 rpm. The friction stir welded ultimate tensile strength Decreases as the volume fraction increases of SiCp (18 wt.%).

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