Stability of Metal Matrix Composite Pads During High-Speed Braking

2018 ◽  
Vol 66 (2) ◽  
Author(s):  
Tao Peng ◽  
Qingzhi Yan ◽  
Xiaolu Zhang
2020 ◽  
Vol 29 ◽  
pp. 2633366X2096249 ◽  
Author(s):  
P Sangaravadivel ◽  
G Rajamurugan ◽  
Prabu Krishnasamy

The phosphor bronze (PB) is widely preferred in various engineering applications due to its high strength, toughness, fine grain size, low coefficient of friction, and better corrosion resistance. The present work is to investigate the effect of tungsten disulfide (WS2) solid lubricant particle reinforcement in the phosphor bronze metal matrix composite (PBMC) through the mechanical and machining characteristics. The different variant of the composite is fabricated using stir casting technique by varying the volume percentage of WS2 particle from 0% to10%. The prepared PBMC samples are subjected to mechanical and machining (boring and high-speed turning) characterizations. The hardness (Brinell hardness) and flexural strength of the composites are examined as per the ASTM standard. The surface roughness (Ra) of the PBMC sample is analyzed through the boring and high-speed turning operations by varying the spindle speed, feed rate, and depth of cut. The scanning electron microscope (SEM) is employed to confirm the uniform dispersion of the reinforcement particle through the microstructural analysis. The presence of WS2 particles and other ingredients is ensured by X-ray diffraction analysis in the composites. The influence of WS2 reinforcement particles on tool life is analyzed on the PBMC4 (PBMC with 8% WS2) with the predefined machining parameters in the high-speed turning operation. The increase in WS2 particle (0–10%) improves the hardness (11.85%) and flexural strength in PBMC4 as compared to PBMC1 (PBMC with 0% WS2). At a higher spindle speed (1200 r/min), the Ra is reduced in PBMC1 as compared to 900 r/min, whereas the rest of the PBMC sample show higher surface irregularity at 1200 r/min.


2014 ◽  
Vol 6 ◽  
pp. 854-862
Author(s):  
Mohd Hadzley Abu Bakar ◽  
Raja Izamshah Raja Abdullah ◽  
Mohd Amran Md. Ali ◽  
Mohd Shahir Kasim ◽  
Mohd Amri Sulaiman ◽  
...  

Author(s):  
M. G. Burke ◽  
M. N. Gungor ◽  
P. K. Liaw

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.


2019 ◽  
Vol 13 (4) ◽  
pp. 5804-5817
Author(s):  
Ibrahim Sabry

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.%).


2013 ◽  
Vol 58 (3) ◽  
pp. 659-662 ◽  
Author(s):  
K. Gawdzińska

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.


Sign in / Sign up

Export Citation Format

Share Document