Rotary Friction Welding of Dissimilar Joints between SSM356 and SSM6061 Aluminium Alloys Produced by GISS

The objective of research is to investigate the parameters, microstructure and mechanical properties of butt joint SSM356 with SSM6061 aluminum alloy by using RFW processes. The main parameters for rotation speeds are 1550, 1700 and 1850 rpm and for burn of length are 2, 2.5 and 3 mm respectively. After experiment, we found that both materials showed strong weld ability although it has a different chemical composition. The microstructural changes in welded metals caused deformation leading to smaller particle sizes. The average Mg2Si particle size was at 0.998 µm long and the width of this particle was at 1.021 µm when it was rotated at 1850 rpm with burn of length at 2.5 mm. The maximum average tensile strength is 87.24 MPa, efficiency of the weld joints is 51.89 percent compared with the base metal of SSM356 aluminum alloys (base metal is 168.12 MPa), and efficiency of the weld joints is 68.45 percent compared with the base metal of SSM6061 aluminum alloys (base metal is 127.44 MPa). Besides, the small particle distribution in the welded metal promotes the hardness property increasing up to 65.56 HV

Evaluation of Microstructure and Mechanical Properties in Dissimilar Joint of SSM7075 with SSM356 Aluminum Alloy using Diffusion Bonding

The aim of this study is to investigate joining parameters that affect microstructure and mechanical properties of diffusion bonding technique in dissimilar joints between SSM7075 and SSM356 aluminum alloys. Diffusion bonding methods were investigated by joining parameters as follows: contact pressure at 3 MPa, holding time 60 and 120 minutes and temperature at 673, 723, 773 and 823 K respectively, under argon atmosphere at 4 litres per minute. After experiments, the results of the investigation have shown that a condition used contact pressure at 3 MPa, holding time 120 minutes, and temperature at 773 K is complete and no defects and voids. Examination of the joint region using SEM and EDX showed that the microstructure in weld zone after welding is globular structure, and eutectics phases of two materials diffuse together. In weld zone, it was found that formation of eutectic phases has Al2CuMg, Mg2Si and Al2Mg2Zn3 phases along the bond interface, distributed throughout bond interface. The tensile tested showed the maximum tensile strength of 94.94 MPa. The hardness was tested for optimum hardness value, 121.20 HV. However, the heat during welding, resulting in precipitation within the aluminum matrix (α-Al), led to increased hardness after diffusion bonding

The Design of Experimental Production of Briquette Solid Fuel from Oil Palm Fiber and Kernel Meal Residual

The objective of this research was to study the experimental design for the production of briquette solid fuel from oil palm fiber and kernel meal residue by Factorial Design. Independent variables consisted of mixture ratio of oil palm fiber to oil palm kernel meal residue, percent of coordinate volume and the briquette forming pressure whereas the dependent variables were composed of compression resistance value, impact resistance value and combustion rate. The results of the experimental design showed that at 20 tons of forming pressure, the mixture ratio of kernel meal residue to oil palm fiber 80:20 and 20 percent of coordinate volume provided the best compression resistance value of 2,636 Newton with 85.75% impact resistance value, combustion rate of 1.71 Grams/Minute, heating value of 4386.3 Calories/Gram and the density of 700 Kilograms/Cubic Meter

The Influence of Parameters Affecting Mechanical Properties and Microstructures of Semi-Solid-Metal 7075 Aluminum Alloy by Using Friction Stir Spot Welding

This research aims to study the influence of parameters that affect the mechanical properties of semi-solid-metal 7075 aluminum alloy with friction stir spot welding process. The parameters fort this experiment such as rotation welding speed at 380, 760, 1240 and 2500 rpm and rotation welding time at 60, 90 and 120 seconds were employed respectively. The study found that the welded specimens at all the conditions can be welded very well. Moreover, friction stir spot welding process showed that the hardness in weld zone had an average value at 79.83 HV which is lower than the hardness of the base metal. The shear tensile strength of the welded specimens had the average value approximately 194.20 MPa at rotation welding speed of 1240 rpm, rotation welding time of 120 seconds and plunge of depth of 2 millimetres. The microstructure in the weld zone and thermal mechanical affected zone were deformed permanently. Therefore, friction stir spot welding process of this aluminum alloy provided good effects on mechanical properties. Statistical analysis showed that the coefficient of determination R-square was equal to 93.50 percent. This means that the variations of the experiments were controllable, such as equipment or other factors in the experiment. For the remaining, only 6.50 percent was uncontrolled factors

Determination of Optimal Parameters for Diffusion Bonding of Semi-Solid Casting Aluminium Alloy by Response Surface Methodology

Liquid state welding techniques available are prone to gas porosity problems. To avoid this solid state bonding is usually an alternative of preference. Among solid state bonding techniques, diffusion bonding is often employed in aluminium alloy automotive parts welding in order to enhance their mechanical properties. However, there has been no standard procedure nor has there been any definitive criterion for judicious welding parameters setting. It is thus a matter of importance to find the set of optimal parameters for effective diffusion bonding. This work proposes the use of response surface methodology in determining such a set of optimal parameters. Response surface methodology is more efficient in dealing with complex process compared with other techniques available. There are two variations of response surface methodology. The one adopted in this work is the central composite design approach. This is because when the initial upper and lower bounds of the desired parameters are exceeded the central composite design approach is still capable of yielding the optimal values of the parameters that appear to be out of the initially preset range. Results from the experiments show that the pressing pressure and the holding time affect the tensile strength of jointing. The data obtained from the experiment fits well to a quadratic equation with high coefficient of determination (R2 = 94.21%). It is found that the optimal parameters in the process of jointing semi-solid casting aluminium alloy by using diffusion bonding are the pressing pressure of 2.06 MPa and 214 minutes of the holding time in order to achieve the highest tensile strength of 142.65 MP

Determination of Optimal Parameters for Diffusion Bonding of Semi-Solid Casting Aluminium Alloy by Response Surface Methodology

Liquid state welding techniques available are prone to gas porosity problems. To avoid this solid state bonding is usually an alternative of preference. Among solid state bonding techniques, diffusion bonding is often employed in aluminium alloy automotive parts welding in order to enhance their mechanical properties. However, there has been no standard procedure nor has there been any definitive criterion for judicious welding parameters setting. It is thus a matter of importance to find the set of optimal parameters for effective diffusion bonding. This work proposes the use of response surface methodology in determining such a set of optimal parameters. Response surface methodology is more efficient in dealing with complex process compared with other techniques available. There are two variations of response surface methodology. The one adopted in this work is the central composite design approach. This is because when the initial upper and lower bounds of the desired parameters are exceeded the central composite design approach is still capable of yielding the optimal values of the parameters that appear to be out of the initially preset range. Results from the experiments show that the pressing pressure and the holding time affect the tensile strength of jointing. The data obtained from the experiment fits well to a quadratic equation with high coefficient of determination (R2 = 94.21%). It is found that the optimal parameters in the process of jointing semi-solid casting aluminium alloy by using diffusion bonding are the pressing pressure of 2.06 MPa and 214 minutes of the holding time in order to achieve the highest tensile strength of 142.65 MP

A Study of the Essential Parameters of Friction-Stir Spot Welding That Affect the D/W Ratio of SSM6061 Aluminum Alloy

This study aimed to investigate how the depth-to-width (D/W) ratio of the welding area affects the welding quality of the SSM6061 aluminum alloy via the friction-stir spot welding (FSSW) process. The results showed that a higher D/W ratio directly results in better mechanical properties. If the D/W ratio value is high (at 1.494), then this leads to higher tensile shear strength at 2.25 kN. On the other hand, if the D/W ratio values are low (at 1.144), then this reduces tensile shear strength to 1.17 kN. The fracture surface behavior on the ring zone also affects the characteristics of ductile fracture. During Vickers hardness analysis, the hardness profiles are in the shape of a W; the maximum hardness was 71.97 HV, resulting from the rotation speed of 3500 rpm and the dwell time of 28 s, where the hardness of the base metal was at 67.18 HV. Finite element (FEM) analysis indicated that the maximum temperature during simulation was 467 °C in the region near the edge shoulder tool, which is 72.96% of the melting point. According to FEM simulation, the temperature under the tool pin region was 369 °C. The generated heat was sufficient to induce changes in the microstructure. For microstructure changes, the globular grain took on a rosette-like form, and coarse grains were observed in the thermal mechanical affect zone (TMAZ) and in the nugget zone (NZ), transforming in the mix zone. Hooks, kissing bonds, voids, and porosity are the defects found in this experiment. These defects indicate a discontinuity in the NZ that leads to worse mechanical properties. During examination via SEM and energy dispersive X-ray (EDX) analysis, the recrystallization structure from β-Mg2Si IMCs to Al3Mg2 and Al12Mg17 IMCs was observed. The size was reduced to an average width of 1–2 µm and an average length of 2–17 µm. Simultaneously, the oxides from the ambient atmosphere present during welding showed dominant partial elements from SiO2, MgO, and Al2O3

Design Analysis of Overhead Crane for Maintenance Workshop

This research aimed to study the design of the overhead crane of a small fishing boat maintenance factory according to the building and functional requirements of the project based on the ASME B30.2-2005 Standard. The results of the study showed that the design of the runway with steel structure BS: 5950: 2000 grade s460 provided vertical and horizontal deflection values of 4.96 and 16.62 respectively that did not exceed the allowed deflection. It is strong enough for use in construction when the stresses on the beam bridge were analysed by the finite element program compared with the strength of the reinforced steel providing a safety value of 1.83