Aluminum/SiC/Nickel-Coated Graphite Hybrid Composites and their Wear Behavior

2012 ◽  
Vol 509 ◽  
pp. 10-11 ◽  
Author(s):  
M.L. Ted Guo ◽  
C.Y.A. Tsao

New materials for high performance tribological applications have been one of the major incentives for the development of aluminum-based metal matrix composites (MMCs). MMCs have received attention because of their improved specific strength, good wear resistance, higher thermal conductivity than ceramics, lower coefficient of thermal expansion, etc. Traditionally, lubricant externally added plays an important role in reducing wear in the application of wear resistance materials. However, self-lubricating materials are more desired than materials to which lubricant needs to be applied periodically, especially for wear parts difficult to be accessed, since solid lubricant contained in the former can be released automatically during the wear process and reduces wear.

2018 ◽  
Vol 167 ◽  
pp. 02010 ◽  
Author(s):  
İsmail Ovalı ◽  
Cemal Esen ◽  
Sevda Albayrak ◽  
Halil Karakoç

In the present study, hybrid metal matrix composites, Al2024/10Al2O3, Al2024/10Al2O3/3MgO, Al2024/10Al2O3/6MgO, Al2024/10Al2O3/3MgO/1.5 Gr, Al2024/10Al2O3/3MgO/3Gr, and reinforcement samples (AA 2024) produced with powder metallurgy process. AA 2024 and reinforcement powders were determined mixture rations and separately mixed during 30 minutes in a three-dimensional Turbula mixer. The mixed compositions were pressed at 300 MPa and sintered at 550°C during 1 h. After that, three materials were extruded at the same temperature. Experimental results show that hybrid metal matrix composites (HMMCs) a better wear resistance than the reinforcement samples because of higher hardness. Gr behave as a lubricant during wear process. The wear resistance of HMMCs can be optimized with controlling of the reinforcement content and type.


Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 738 ◽  
Author(s):  
Qiong Xu ◽  
Aibin Ma ◽  
Junjie Wang ◽  
Jiapeng Sun ◽  
Jinghua Jiang ◽  
...  

Relatively low compactness and unsatisfactory uniformity of reinforced particles severely restrict the performance and widespread industry applications of the powder metallurgy (PM) metal matrix composites (MMCs). Here, we developed a combined processing route of PM and equal channel angular pressing (ECAP) to enhance the mechanical properties and wear resistance of the SiCp/Al-Si composite. The results indicate that ECAP significantly refined the matrix grains, eliminated pores and promoted the uniformity of the reinforcement particles. After 8p-ECAP, the SiCp/Al-Si composite consisted of ultrafine Al matrix grains (600 nm) modified by uniformly-dispersed Si and SiCp particles, and the composite relative density approached 100%. The hardness and wear resistance of the 8p-ECAP SiCp/Al-Si composite were markedly improved compared to the PM composite. More ECAP passes continued a trend of improvement for the wear resistance and hardness. Moreover, while abrasion and delamination dominated the wear of PM composites, less severe adhesive wear and fatigue mechanisms played more important roles in the wear of PM-ECAP composites. This study demonstrates a new approach to designing wear-resistant Al-MMCs and is readily applicable to other Al-MMCs.


Author(s):  
Theerkka tharaisanan Rajamanickam ◽  
Kathiresan Marimuthu

Aluminium metal matrix composites (AMMC’s) have been widely used because of their superior properties like high strength to wear ratio, high wear resistance, and higher heat conduction rate. The additions of reinforcements in the form of discontinuous particles lead to an increase in the properties of Metal Matrix Composites (MMC). In this present work, the ALMMC composite was fabricated with the addition of discontinuous reinforcement particles of Zirconium Carbide (ZrC) and Boron Carbide (B4C). The mechanical properties such as tensile strength, hardness, and impact strength were tested as per the ASTM standards. The tribological properties were tested using a pin-on-disc setup under different loading conditions (10, 20, 30, 40 N). Moreover, the morphological characterization of ALMMC was carried out by using the Scanning Electron Microscope (SEM) analysis. Furthermore, the Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) was accomplished to find the thermal stability of ALMMC. The findings show that the variations of reinforcement of ZrC added had given improved properties like hardness, tensile strength, impact strength and wear resistance.


2017 ◽  
Vol 7 (1.1) ◽  
pp. 193
Author(s):  
M.H. Faisal ◽  
S. Prabagaran ◽  
T.S. Vishnu

Aluminium/graphite composites are the need of modern times for addressing the fuel saving issues. The graphite in such composites act as solid lubricant and it reduce external fuel requirements. But such composites are having degraded mechanical properties due to the graphite content in composite. In order to solve the negative effect of graphite on mechanical properties of LM13/Gr self-lubricating composite this study was conducted to find out the mechanical properties of LM13/B4C/Gr Metal Matrix Composites. Boron carbide was selected as reinforcement because of its better reinforcement properties compared to alumina and silicon carbide. The properties of the hybrid composites were compared with the LM13/Gr self-lubricating composite to study the enhancement in mechanical properties that has been caused by the boron carbide particles. Using computerized universal testing machine and rock-well hardness tester mechanical properties such as hardness and tensile strength were tested. Pin on disk testing machine was used to analyse the wear behavior. The test results indicates that by raising weight % of boron carbide particles in the LM13, tensile strength and hardness of the hybrid composites was increased compared to self-lubricating composite accompanied by better tribological properties.


Author(s):  
Anitha Santhoshi Madugula ◽  
B. Murali Krishna ◽  
G. Swaminaidu

Red mud emerges as the major waste material during the production of alumina from bauxite and its potential as a filler material in metal matrices has not yet been reported. In view of this, an attempt is made to explore the possibility of making a class of wear resistant metal matrix hybrid composites with nano-structured red mud and micro sized fly ash particles as reinforcement. The micro-sized red mud particles have been modified to nano-structured red mud using high energy ball milling and after 30 hours of milling, the size was reduced from 100 microns to 30 nm. Composites were fabricated by stir casting and experiments were conducted under laboratory condition to assess the wear characteristics of AA2024- 15 wt% fly ash (micro-sized) and varying fractions (2 wt%, 4 wt% and 6 wt%) red mud (nano-structured) hybrid composites under different working conditions in pure sliding mode on a pin-on-disc machine. Tests were conducted with sliding speeds of 200 rpm, 400 rpm and 600 rpm at loads of 10N, 20N and 30N. The increased frictional thrust at higher load results in increased de-bonding and caused easy removal of material and hence the wear rate is increased with increase in normal load. The wear resistance of the composite is increased with increase in red mud fraction. This is due to the increase in surface energy and inter-atomic bonding with increase in nano-structured red mud fraction. The addition of redmud particles to the matrix phase causes dispersion strengthening and hence the strength as well. Wear resistance is increased with increase in redmud fraction.


2014 ◽  
Vol 984-985 ◽  
pp. 536-540
Author(s):  
K. Umanath ◽  
S.T. Selvamani ◽  
K. Palanikumar ◽  
T. Raphael

Aerospace industry and automobile industries are enhanced performance necessary for materials with better qualities compare to conservative materials. In automotive areas, this is predominantly factual for power train employed as conflicting to body application. For each kind of appliance, description such as hardness of the material, wear resistance, temperature withstands ability, plasticity, fracture, fatigue strength, etc. It must be as high as possible, while parameters such as density and cost must be minimized; the latter is of general concern for automobile use and relatively inexpensive light aircraft. Because of their low density, the light metals based on aluminum, magnesium, and titanium are particularly attractive for both types of applications. In this paper, advanced material of Al6061/SiC/Al2O3hybrid composites is discussed, followed by a consideration of advanced material specifically in aerospace and automotive applications. Processing the lightweight metal, with enhanced hardness properties is presented.


2018 ◽  
Vol 25 (2) ◽  
pp. 213-228 ◽  
Author(s):  
Ashish Kumar Srivastava ◽  
Amit Rai Dixit ◽  
Sandeep Tiwari

AbstractMetal matrix composites (MMCs) are the new-generation advanced materials that have excellent mechanical properties, such as high specific strength, strong hardness, and strong resistance to wear and corrosion. All these qualities make MMCs suitable material in the manufacture of automobiles and aircraft. The machining of these materials is still difficult due to the abrasive nature of the reinforced particles and hardness of MMCs. The conventional machining of MMCs results in high tool wear and slow removal of materials, thereby increasing the overall machining cost. The nonconventional machining of these materials, on the contrary, ensures much better performance. This paper reviews various research works on the development of MMCs and the subsequent hybrid composites and evaluates their performances. Further, it discusses the influence of the process parameters of conventional and nonconventional machining on the performance of MMCs. At the end, it identifies the research gaps and future scopes for further investigations in this field.


2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Ridvan Gecu ◽  
Ahmet Karaaslan

This study aims to investigate the effect of volume fraction of commercially pure titanium (CP-Ti) on microstructural, mechanical, and tribological features of A356 aluminum matrix composites. Vacuum-assisted melt infiltration casting was performed to produce composites with 50%, 65%, 75%, and 80% CP-Ti contents. CP-Ti sawdusts were assembled under mechanical pressure in order to attain porous one-piece CP-Ti preforms which were infiltrated by A356 melt at 730 °C under 10−5 Pa vacuum atmosphere. TiAl3 layer was formed at the interface between A356 and CP-Ti phases. Owing to increased diffusion time through decreased diffusion path length, both thickness and hardness of TiAl3 phase were increased with increasing CP-Ti ratio, whereas the best wear resistance was obtained at 65% CP-Ti ratio. The main reason for decrease in wear resistance of 75% and 80% CP-Ti reinforced composites was fragmentation of TiAl3 layer during wear process due to its excessively increased brittleness. Strongly bonded TiAl3 phase at the interface provided better wear resistance, while weakly bonded ones caused to multiply wear rate.


Author(s):  
S A Mohan Krishna ◽  
T N Shridhar ◽  
L Krishnamurthy ◽  
K B Vinay ◽  
G V Naveen Prakash

Aluminium matrix composites belong to the family of materials whose mechanical, tribological, thermal and electrical properties can be customized effectively. Most of the commercial work on MMCs has been highlighted on Aluminium as the matrix material. The combination of light weight, environmental resistance and beneficial mechanical properties has made Aluminium alloys exceedingly popular; these properties also make Aluminium best suited for use as a matrix metal. The thermophysical properties of these composites can be tailor made and have excellent specific mechanical properties. These composites can be fabricated with ease. Aluminium matrix composites reinforced with the particles of Silicon Carbide possess high yield strength, low coefficient of thermal expansion or thermal expansivity, high modulus of elasticity and excellent wear resistance by maintaining volume proportion up to 20%. Aluminium hybrid composites can be customized to provide moderate Coefficient of Thermal Expansion (CTE) and high thermal conductivity that are favorable for the applications pertaining to thermal management equipment. However, it is necessary to evaluate different percentage combinations of reinforcements with matrix Aluminium to check for thermal stability and to measure thermal conductivity and coefficient of thermal expansion. It is expected that, Aluminium-Silicon Carbide-Graphite hybrid composites can be used as load bearing material for the above applications. In this paper, a review about the said hybrid composites to investigate thermal properties for engineering applications have been discussed based on its technological relevance, applications and research prospect.


2017 ◽  
Vol 13 (3) ◽  
pp. 32-36
Author(s):  
S. Rajesh ◽  
C. Velmurugan

Metal matrix composite (MMC) focuses primarily on improved specific strength, high temperature and wear resistance application. Aluminum matrix reinforced with titanium carbide and molybdenum disulfide has good potential and also self-lubrication. The main challenge is to produce this composite in a cost effective way to meet the above requirements. In this study Al–TiC-MoS2 castings with different volume fraction of TiC and MoS2 were produced in an argon atmosphere by an enhanced stir casting method. Hardness of the composite has increased with higher % of TiC addition. At that same time self-lubrication of composite has occur in the effort of MoS2. Dry sliding wear behavior of AMC was analyses with the help of a pin on disc wear and friction monitor. The present analyses reveal the improved hardness  as well as wear resistance.


Sign in / Sign up

Export Citation Format

Share Document