Abdul Maleque

Effect of variable particle size reinforcement on mechanical and wear properties of 6061Al–SiCp composite

Abstract The influence of reinforcement particle size variation plays a major role on the properties of Al–SiCp composite. Therefore, this study aim to investigate the mechanical and wear performance of single particle size (SPS) and multiple particle size (MPS) Al–SiCp composite prepared by stir casting process. The SPS comprises three categories; fine (15 μm), intermediate (40 μm) and coarse (80 μm) particle sizes and combination of the three sizes accounts for the MPS in the ratio 1:1:2, respectively. Oxidation of the SiCp and addition of 1 wt% Mg during composite processing resulted to interface reaction products such as MgO (magnesium oxide) and MgAl2O4 (magnesium aluminate) which suppresses the potential formation of undesired Al3C4 (aluminium carbide). The study reveals that MPS composite improved the hardness and impact properties with enhanced wear performance compared to SPS composite. Characterization of the composite morphology and phases was performed using scanning electron microscope and X-ray diffraction analysis. This study provides an effective method of optimizing the properties of Al–SiCp composite by integrating MPS with low volume fraction of reinforcement phase.

Flexural and Impact Properties of Kenaf-Glass Hybrid Composite

This paper investigates the flexural and impact properties of kenaf-glass (KG) fibers reinforced unsaturated polyester (UPE) hybrid composite on a source of green composite. The matrix is kept constant with 70 % volume fraction while kenaf and glass fibers were varied, such as 7.5/22.5 v/v, 15/15 v/v and 22.5/7.5 v/v. The 30 % kenaf and 30 % glass are also used for the preparation of composite materials. The kenaf fiber was treated with 6% sodium hydroxide (NaOH) diluted solution for 3 hours. Hybrid composites are fabricated using sheet molding compound (SMC) process. The mechanical tests, such as flexural and impact are performed using ASTM D790-03 and ASTM D256-04 respectively. The study showed that the highest flexural strength was obtained from treated kenaf with 15/15 v/v KG fiber reinforced hybrid composite while untreated of 15/15 v/v KG composite showed the highest value of impact strength in this investigation. This can be concluded that 15/15 v/v KG fiber reinforced unsaturated polyester hybrid composite is the most appropriate hybrid composite which can be considered for many engineering structural applications, such as automotive, aerospace, construction or sports.

Wear behaviour of TiC coated AISI 4340 steel produced by TIG surface melting

Coating possesses superior wear resistance which makes the material suitable for components subjected to dynamic applications under sever wearing condition and high temperature applications. In this study, TiC coating layer was synthesized by preplacing a 1 mg/mm2 of fine size (~40 μm) TiC powder on the surface of AISI 4340 steel. The composite layer was produced by rapidly melting TiC powder together with the substrate steel using tungsten inert gas (TIG) torch welding at a fixed heat input of 1344 J/mm. The wear behaviour of the coated steel was investigated using a universal pin-on-disc tribometer. The microhardness profile of the coating showed increment of the hardness value (almost 5 times higher) than the substrate material. The wear test results showed that the TiC coated steel has lower wear volume loss hence, higher wear resistance compared to the substrate AISI 4340 steel. Incorporation of TiC into the steel surface has improved the wear behaviour of the steel by reduction of plastic deformation and ploughing of the steel surface. The SEM micrograph of the wear worn surface showed mild type of abrasive wear for coated steel whereas, the AISI 4340 steel showed severe type wear with excessive plastic deformation and ploughing.

TIG Melted Surface Modified Titanium Alloy for Automotive Cylinder Liner Application / TIG Eritilmiş Yüzey Otomotiv Silindir Liner Uygulaması Titanyum Alaşım Modifiye

Fe-bazli alasim tungsten tesirsiz gaz (TIG), yuzey modifikasyonu asinma ve metalik bileseni malzeme asinmasina karsi koruma saglayabilir. Bu calismada, bir girisim asinma substratin direncini gelistirmek icin TIG torc eritme islemi ile Ticari saflikta bir titanyum (CP-Ti) ile ilgili tozlar onceden yerlestirilmis Fe-C-Si cokelmesini kesfetmek icin yapilmistir. Uc farkli toz 97Fe2C1Si nominal bilesimi ile harmanlayarak, 94Fe 4C2Si ve 91Fe6C3Si ayri geleneksel 100 A uretilen TIG kaynak mesale ve enerji girisi 1350 J / mm kullanilarak CP-Ti erimis bulundu. Sonuclarin analizi TIG mesale alt tabaka ile iyi metalurjik bag ile erime havuzlar geometri urettigini gosterdi. Eriyik mikro farkli TiC cokeltilerin olusuyordu. Gozenekler bariz yuksek karbon icerigi (94Fe 4C2Si) ile yuzey modifikasyonu sonrasinda eriyik mikro goruldu. Hem mikrosertlik ve asinma ozelligi ozellikle 94Fe4C2Si ile TIG kaplama sonrasi onemli bir gelisme gosterdi. Bu nedenle, Fe-C-Si, optimize edilmis bir bilesim olup asinma direncini kontrol etmek icin iyi bir bilesim ve silindirik astar uygulanmasi icin TIG erimesi altinda 94Fe4C2Si ile toz onceden yerlestirilmis oldugu gorulmektedir.

TIG melted surface modified titanium alloy for automotive cylinder liner application

Fe-bazli alasim tungsten tesirsiz gaz (TIG), yuzey modifikasyonu asinma ve metalik bileseni malzeme asinmasina karsi koruma saglayabilir. Bu calismada, bir girisim asinma substratin direncini gelistirmek icin TIG torc eritme islemi ile Ticari saflikta bir titanyum (CP-Ti) ile ilgili tozlar onceden yerlestirilmis Fe-C-Si cokelmesini kesfetmek icin yapilmistir. Uc farkli toz 97Fe2C1Si nominal bilesimi ile harmanlayarak, 94Fe 4C2Si ve 91Fe6C3Si ayri geleneksel 100 A uretilen TIG kaynak mesale ve enerji girisi 1350 J / mm kullanilarak CP-Ti erimis bulundu. Sonuclarin analizi TIG mesale alt tabaka ile iyi metalurjik bag ile erime havuzlar geometri urettigini gosterdi. Eriyik mikro farkli TiC cokeltilerin olusuyordu. Gozenekler bariz yuksek karbon icerigi (94Fe 4C2Si) ile yuzey modifikasyonu sonrasinda eriyik mikro goruldu. Hem mikrosertlik ve asinma ozelligi ozellikle 94Fe4C2Si ile TIG kaplama sonrasi onemli bir gelisme gosterdi. Bu nedenle, Fe-C-Si, optimize edilmis bir bilesim olup asinma direncini kontrol etmek icin iyi bir bilesim ve silindirik astar uygulanmasi icin TIG erimesi altinda 94Fe4C2Si ile toz onceden yerlestirilmis oldugu gorulmektedir.

Effect of Ball Milling Parameters on the Synthesization of Carbon Nanotube Aluminium Nano Composite

Recently, carbon nanotubes (CNTs) are attracting much interest as fibrous materials for reinforcing aluminium matrix composites due to unique properties such as high strength, elastic modulus, flexibility and high aspect ratios. However, the quality of the dispersion is the major concern factor which determines the homogeneity of the enhanced mechanical and tribological properties of the composite. This work study and characterized the nanocomposite prepared with different weight percentage of CNT in aluminium matrix using powder metallurgy route under high energy planetary ball milling operations. The ball milling was performed for three hours at different milling speeds and under controlled atmosphere. The experimental results showed homogeneous dispersion of CNTs in aluminium matrix at 300 rpm. The preliminary mixing of CNTs and aluminium powder in a tube via manual shaking could be the main contributing factor in achieving uniform dispersion of CNT in aluminium matrix after ball milling. The addition of ethanol as a process control agent reduced the agglomeration of CNTs in the matrix. Control atmosphere during milling also prevented the formation of inter metallic compounds such as aluminium carbide in the composite.

Micro Electro Discharge Machining of Non-Conductive Ceramic

Electro discharge machining (EDM) as a die sinking process has taken off in 1943. Since then it was known as a non-conventional machining process and its application was limited for processing only electrically conductive materials. Later on, due to the widespread applications, this EDM process is considered conventional as usual. However, in the recent years EDM has gone through considerable changes especially with dielectric fluids, simple to complex geometry, meso to micro sized structures, nanometric surface finish, and so on. In addition, the application of EDM has also been extended for processing electrically semi-conductive and non-conductive materials like ceramics and composites. This paper discussed micro electro discharge machining of non-conductive ceramic materials. It includes detail process development, modelling of material removal rate and surface finish which include the effect of multi spark and random spalling conditions.

Effect of Copper on Tensile Strength Improvement of Al-Cu-SiCP New Composite

The composite materials with 2, 4 and 6 % Cu were developed using a noble stir casting method. Tensile test was conducted using universal tensile test machine according to ASTM-2002 (E8M-01) standard and the fracture surface was analysed using scanning electron microscope (SEM). The result showed that the ultimate tensile strength (UTS) was increased due to the percentage increment of Cu in the Al-Cu matrix. A significant change in UTS was observed from 2 to 4 % Cu whereas slight improvement was seen from 4 to 6 % Cu addition. The SEM micrograph of the fracture surface reveals that the cracks were propagated in the fibrous zone resulting from the initiation of micro voids between the matrix and particle interfaces. The number and size of dimples for 2% Cu were considerably lower and the facet features were noticeably higher than higher Cu content composition, whereas, the dimple and facet size and number for the 4% Cu are very close to the 6% Cu content composite which may play important role in the improvement of tensile strength. These findings tinted for the potential application of SiCp reinforced Cu influenced Al-Cu-SiCp composite for automotive engine components and other similar applications as well.

Synergistic Effect on Flexural Properties of Kenaf-Glass Hybrid Composite

This paper presents the synergistic effect on flexural properties of kenaf-glass (KG) mat reinforced unsaturated polyester (UPE) hybrid composite which can compounded using sheet molding compound (SMC) process. The matrix is kept constant with 70 % volume fraction while kenaf and glass fibers were varied, such as 7.5/22.5 v/v, 15/15 v/v and 22.5/7.5 v/v. The 30 % kenaf and 30 % glass are also used for the preparation of composite materials. The kenaf mat was treated with 6% sodium hydroxide (NaOH) diluted solution for 3 hours. This mercerization process improved the interface by interacting with both the fiber and its matrix. The flexural test was performed using ASTM D790-03 standard. The study showed with the addition of kenaf and glass mat 15/15 v/v, the optimum flexural properties was obtained compared to other composition. This can be concluded that 15/15 v/v KG mat reinforced unsaturated polyester hybrid composite is the most appropriate hybrid composite which can be considered for many engineering structural applications mainly in automotive panel, bottom structure and bumper beam.

The Crystallinity and Hardness Properties of Al-Cu/SiCp New Composite Materials

The main aim of this paper is to investigate the crystallinity and hardness properties of Al-Cu/SiCp matrix composite (AMC) materials. The materials were prepared using a noble stir casting technique by varying the percentage of Cu in the Al-Cu matrix. Qualitative X-ray analysis has been carried out to characterize the crystallinity of the Al-Cu/SiCp as-cast composite materials. Sample was cut and shaped into 25 mm×15 mm×4 mm in dimension then polished with diamond paste. X-ray diffraction diagrams were recorded using a transmission technique with a SHIMADZU Lab X (XRD-6000) X-ray generator operating at Cu Kα1 radiation. Hardness test was conducted using Vickers hardness tester (Mitutuyo, MVK-H2). The results indicated that a significant crystal growth was occurred in the composite materials due to increase of Cu from 2 to 4 % whereas a slight improvement of crystallinity was observed when the Cu percentage was increased from 4 to 6 % in the matrix. It was also revealed from the result that a similar trend was grasped in hardness increment with the crystallinity of Al-Cu/SiCp AMCs.