Influence of Polymer Waste (Polyethylene Terephthalate) in Composites Structure Materials

Nowadays the use of insulation wall in building construction faces some problems such as having high weight, very reflective sound, heat transfer (the effectiveness of heat conductivity) incompetent and mechanical properties (strength) limited. The sounds which impinge the wall cannot be absorbed efficiently but instead gives high reflection. This causes some noise on high echo in a room. So a good acoustic insulation must be efficient in absorbing the sound. This project proposes lightweight concrete as a replacement for insulation wall. This lightweight concrete will be developed using thermoplastic polymer waste which is recycle plastic bottles, sand, water, and cement. This research was used thermoplastic polymer waste which is PET (Polyethylene Terephthalate) material as the reinforcement material to replace small gravel in lightweight concrete. All its composition percentage of raw materials was divided into different samples composition. Its composition determines the performances of the samples in thermal conductivity coefficient, density, porosity and mechanical properties (strength and bending performance)

The Evaluation of Machinability and Surface Texture of Tool Steel with Copper Electrode in Electro Discharge Machining

The study reported in this thesis is a contribution towards the understanding on the relationship of Electro Discharge Machining (EDM) parameters in machining of tool steel. Some of the main parameters controlling material removal rate (MRR) in EDM, namely supply current, pulse on/off duration and electrode size with electrode wear rate (EWR) are studied and their effects on the machinability factors (MRR and EWR) are evaluated. The surface finish in term of surface texture, which determined by the roughness measurement on the machined surface (Ra) is also studied. Further, volumetric wear (VW) as the three-dimensional analysis among MRR, EWR and machining time or pulse on/off duration is analyzed. In the experiment using the die-sinking EDM, tool steel and copper were selected as the workpiece and electrode, respectively. Three sizes of copper electrode were used: diameter of 5 mm, 10 mm and 15 mm and two experimental setups were prepared. In setup-I, those electrodes were used to produce blind hole machining features at supply currents of 3A and 6A for machining time from 5 to 20 minutes, while pulse on/off duration was kept constant. In setup-2, machining time was kept constant, supply currents were also 3A and 6A but pulse on/off durations were varied from 6 to 12 J.1S. From the evaluation of MRR, EWR, surface roughness and VW, the results show that the electrode with diameter of 15 mm gives the best performance at all supply currents, machining time and pulse on/ofT durations. The values of MRR and EWR increase as the increasing of machining time, supply current and pulse on/off duration. Surface roughness has no relationship with machining time. In contrast, it has a close relationship with pulse on/off duration where the higher the pulse on/off duration the higher is the magnitude of surface roughness

Plane Strain Fracture Toughness Determination for Magnesium Alloy

A stress intensity factor K was used as a fracture parameter to determine the true material property, i.e. plane strain fracture toughness K of AZ61 magnesium alloy using a single edge notch bend (SENB) specimen in accordance to ASTM E399 testing method. Five different specimen thicknesses of 2 to 10 mm were used in the test. A sharp fatigue pre-crack was initiated and propagated to half of specimen width at a constant crack propagation rate of about 1 x 10-8 m/cycle before the specimen was loaded in tension until the fracture stress is reached and then rapid fracture occurred. The fracture toughness K values obtained for different thicknesses showed that KC value decreased with increasing specimen thickness. The highest KC value obtained was 16.5 MPa√m for 2 mm thickness specimen. The value of K became relatively constant at about 13 MPa√m when the specimen thickness exceeds 8 mm. This value was then considered as the plane strain fracture toughness K of AZ61 magnesium alloy. Calculation of the minimum thickness requirement for plane strain condition and the size of the shear lips of the fracture surface validate the obtained K value

Effect of Thermoplastic Polymer Waste (PET) in Lightweight Concrete

Abstract. Contruction concrete that use of insulation wall in building construction faces some problems such as having high weight, very reflective sound, heat transfer (the effectiveness of heat conductivity) incompetence and mechanical properties (strength) constraints. The sounds which impinge the wall cannot be absorbed efficiently but instead gives high reflection. This causes some noise of high echo in a room. So a good acoustic insulation must be efficient in absorbing the sound. This project proposes lightweight concrete as a replacement for insulation wall. This lightweight concrete will be developed using thermoplastic polymer waste which is recycled plastic bottles, sand, water, and cement. This research used thermoplastic polymer waste which is PET (Polyethylene Terephthalate) material as the reinforcement material to replace small gravel in lightweight concrete. All its composition percentage of raw materials was divided into different samples composition. Its composition determines the performances of the samples in density, porosity and mechanical properties

Effect of Solution Treatment on Fatigue Crack Propagation Behaviour of Magnesium Alloy

An investigation on the effect of solution treatment on fatigue crack propagation (FCP) behaviour of AZ61 magnesium alloy was carried out. A centre cracked plate tension (CCT) specimen was prepared from an extruded cylindrical AZ61 magnesium alloy rod. The solution treatment was performed at 400oC for one hour to get homogeneous solid solution before quench in water. The FCP test was conducted in a laboratory air environment under a constant amplitude sinusoidal loading with a stress ratio of 0.1 and a frequency of 10 Hz. The FCP curve for solution treated samples was then compared to that of the extruded AZ61 magnesium alloy. Results showed that solution treatment shifted the FCP curve to the left and demonstrated a lower fatigue crack propagation resistance at the high stress intensity region. The threshold value was recorded at 0.91 MPa√m

Plane Strain Fracture Toughness Determination for Magnesium Alloy

A stress intensity factor K was used as a fracture parameter to determine the true material property, i.e. plane strain fracture toughness KIC of AZ61 magnesium alloy using a single edge notch bend (SENB) specimen in accordance to ASTM E399 testing method. Five different specimen thicknesses of 2 to 10 mm were used in the test. A sharp fatigue pre-crack was initiated and propagated to half of specimen width at a constant crack propagation rate of about 1 x 10-8 m/cycle before the specimen was loaded in tension until the fracture stress is reached and then rapid fracture occurred. The fracture toughness KC values obtained for different thicknesses showed that KC value decreased with increasing specimen thickness. The highest KC value obtained was 16.5 MPa√m for 2 mm thickness specimen. Thevalue of KC became relatively constant at about 13 MPa√m when the specimen thickness exceeds 8 mm. This value was then considered as the plane strain fracture toughness KIC of AZ61 magnesium alloy. Calculation of the minimum thickness requirement for plane strain condition and the size of the shear lips of the fracture surface validate the obtained KIC value

Effect of Carbon Nanotubes on Properties of Graphite/Carbon Black/Polypropylene Nanocomposites

Abstract. High chemical corrosion, low manufacturing cost and light of total mass of bipolar plate in Proton Exchange Membrane Fuel Cell (PEMFC) lead most of the PEMFC’s researchers over the world attracted their interest to replace pure graphite or metal based bipolar plate with conductive polymer composites (CPCs) bipolar plate. CPCs is fabricate from the mixed of conductive fillers such as and Graphite (G) andCarbon Black (CB) had been incorporated in Polypropylene (PP) matrix for fabrication of electrical conductive polymer composite plate. Most researchers reported only at high loading of fillers (more than 90 wt.%), are gave electrical conductivity above 100 S/cm, which is target from Department of Energy (USA). Higher loading of fillers cause change in rheological properties and increase the difficulties in polymer processing. Thus will decreasing the electrical and mechanical properties of CPCs as bipolar plate. Therefore, in this study carbon nanotubes (CNTs) which have 1000 time electrical conductivity than copper wire are introduced into G/CB/PP composite to compensate above problems. But the main problems of CNTs, at high loading it tend to agglomerate and thus will affect the properties of CPCs. So that, small amount of CNTs which is 0.2, 0.4, 0.6 and 0.8 wt.% will be added into G/CB/PP composite. But weight percentage of CB and PP has been fixed which is 25 wt.% and 20 wt.% respectively and the weight percentage of G will various from 55 wt.% to 54.2 wt.% according to CNTs loading. The result shows that the G/CB/CNTs/PP composite with 0.2 wt% CNTs has the higher electrical conductivity 295.78 S/cm

Failure analysis on hybrid fiber reinforced plastics for bolted joint under geometric parameters effect

In this study, glass fiber and kenaf reinforced thermoplastic hybrid composite were fabricated using compression method. The composite is layout in sandwich structure. Woven glass fiber is sandwiched in between woven kenaf fiber with polypropylene matrix. The nominal thickness of the composite is 3mm. Bolted joint test was conducted according to ASTM D5961 using Universal testing machine. The results confirm geometric parameters affect the failure mode

Failure analysis of two serial holes bolted joint hybrid composite

This study investigates the effect of different geometry parameters to the behavior of bolted-joint hybrid composites. The hot compression method is used to fabricate the hybrid composite. The composites were fabricated with three layers of woven fibers which are two layers of woven glass fiber and a layer of woven kenaf fiber with polypropylene matrix making a composite panel. The nominal thickness of these composites is 3mm and the bearing test is done by using Universal Testing Machine. The test were conducted according to ASTM D5961. The results show the different geometry parameters affect the behavior of hybrid composites

Effect Of Heat Treatment On Microstructure And Mechanical Properties Of Az61 Magnesium Alloys

Magnesium alloys have been increasingly considered as an attractive material in the transportation industry. Extruded magnesium alloys have been found in the center of interest combining their lightweight, surface quality with the wide range of possible achievable geometries. In this study, the AZ61 alloy has been chosen for investigation as one of the most common commercial magnesium wrought alloys. The microstructure change and Mgl7AI2 precipitate in the alloy had been investigated and its influence on hardness had been studied. After primary microstructure characterization and mechanical testing in the as-extruded condition the specimens have been subjected to heat treatment to the temperature 400°C for one hour followed by quenching in the water. Specimens treated were found to have a coarse grain, homogeneous structure with a substantial increase in grain size. Then the specimens are aged at temperature 200°C for half and two hours followed by quench in the water. Optical observations reveal Mg17AI2 precipitations grow in the form of needle shape within the grain after two hour aging. The hardness and mechanical properties of the AZ61 magnesium alloy is also found to increase owing to secondary hardening by precipitation strengthening