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The objective on this research is to investigate the influence of tool rotation to the welding strength of Aluminium and Steel. AA1100 and ST37 were material selected for the specimens. The welding process was conducted by using Friction Stir Welding (FSW) method. The tensile strength and hardness of the specimens will be indicators of welding strength. FSW was carried out by using conventional milling machine with tool rotation of 800 rpm and 1250 rpm. Feed rate 10 mm/minute for all process. The tool tilt angle was 1° and 1.8 mm of depth plunge. By using 800 rpm, the average of Tensile Stress was delivered of 82.22 MPa and Strain of 1.09%. While for the use of 1250 rpm, Tensile Stress given 96.23 MPa and Strain 1.14%. The hardnes of HVN on the weld zone was 42.2 and 56.2 HVN for rotation of 800 and 1250 rpm respectively. Based on the Tensile Stress and the Hardness of the weld zone, the FSW process was influenced by tool rotation. The higher rotation given higher Tensile strength.

The existence of fossil fuels is increasingly scarce nowadays. Therefore, finding alternative fuels to substitute petroleum fuels, especially gasoline that very huge used for a motor vehicle. One of the alternative fuels as a substitute for gasoline is bioethanol (BE). The aim of the research work was to analyze engine performance and exhaust emission level of vehicle using two different types of spark plug. Further investigation was addressed by varying additional bioethanol fuel made from raw material of cassava. The work was carried out experimentally both in the laboratory and engine test drive. The results show that by using platinum spark plug resulting better performance of engine. The additional bioethanol on fuel, the power, and torque generated from the engine increases with the increase of percent bioethanol in the fuel mixture. The fuel consumption is more efficient by using fuel of 30% BE, compared with engine operation using fuel of 100% pertalite. While the results of the exhaust emission on the vehicle show that by using fuel bioethanol, exhaust emissions decrease as the increase of bioethanol in fuel mixture than exhaust emissions generated when using fuel 100% pertalite. It was proved by statistical data analysis using a one-way ANOVA Varian (F test) for power, torque, and HC emission levels, found of F value less than F table. Therefore hypothesis null (Ho) was accepted. Further result in each variation of fuel there is no significant difference. However, for CO, found that counted F greater than F table, then Ho was rejected; therefore the result of each variation of fuel there is significantly different.

Manufacturing of beverage cans is porcessed by using multi-stage ironing following deep drawing from the sheet material of aluminum and steel. An earing profiles are develops during deep drawing of cylindrical cup due to the planar anisotropic properties of sheet. Therefore, the analysis of earing is important to evaluate and control the development of earing. This paper describes a simulation of the cold ironing process in the forming cylinder cap. The ironing process in this study was focused on the prediction of height increasing, earing and thinning. Two different materials of aluminum AA5042 and AKDQ steel were selected for comparison. The results show that the increasing of cup height was in the same trend.

Numerical simulation by finite element method has become a powerful tool in predicting and preventing the unwanted effects of sheet metals technological processing. One of the most important problems in sheet metal forming is the compensation of springback. To improve the accuracy of the formed parts, the die surfaces are required to be optimized so that after springback the geometry falls at the expected shape. This paper presents and discusses numerical simulation procedure of die compensation by using the methods of Simplified Displacement Adjustment (SDA). This analysis use Benchmark 3 models of Numisheet 2011. Sensitively analysis was done by using finite element method (FEM) show that the springback values are influenced by element size, integration points and material properties.

In commercial aerospace development, feasibility accidents design or crashworthiness is a major concern in aviation safety. Fuselage structure plays an important role in absorbing energy during an accident. The research aims are to determine drop test phenomenon on the fuselage, to investigate deformation occurred in the structure of the fuselage, and to know the influence of the airframe falls position to the stress strain which occurred in the structure of the fuselage. This research was conducted by varying the fall angle of the fuselage in a vertical position or 0° and 15°. Fuselage design was modeled by using SolidWorks. Then the model is imported to the Abaqus for drop test simulation. From the simulation results, it can be obtained the phenomenon of deformation on the structure of the fuselage when it comes in contact with the rigid ground. The high deformation occurs shows the structure capabilities in order to absorb the impact. It could be happened because the deformation is influenced by intern...

The objective on the research was to investigate the mechanical properties and microstructure of tailor welded blank (TWB) made from AA6061-T6 and AA1100 using friction stir welding (FSW) process. Due to the dissimilar mechanical properties of the two aluminium alloys, microhardness test was conducted to measure the hardness distribution across the weld nugget. The mixing of two distinct materials was influenced by tool rotation speed. Therefore, microstructure analysis was carried out to investigate the grain size and shape. The grain size of AA6061-T6 has increased in the heat affected zone (HAZ) while for AA1100 has decreased. In the weld nugget, it has found a hook defects in the dissimilar aluminium joining. By using monotonic tensile load, the different weld line direction was observed with the expansion in tool rotation. The joints failure were consistently on the area of AA1100 series. Furthermore, two specimens were investigated, one through the dissimilar aluminium and the other through similiar material. Inspection of the weld nugget hardness was shown that nonhomogen material intermixing during the stiring process as confirmed by microhardness measurement.

The most key factor in the modern sheet metal process is an accurate dimension of final shape part. The accurate simulation of the drawing products will not be useful since springback will occur after the tools are removed off the drawing die set. One of the most promising ways to solve this problem is modify the die surface as known die compensation. Die compensation is one of the hottest topics in the stamping field. In this paper, a new method to compensate the die tool shape due to elastic deviation is proposed. The combination of spring-forward and spring-back method is applied simultaneously. This method was applied to 2D draw bending benchmark problem from Numisheet '93 for verification. The simulation result show that the final deformed part is closely to the desired shape part.

Springback phenomenon theoretically occurs for anything kind of deep drawing or sheet metal forming process. In the real manufacture, it is a well known and avoided characteristic of every process that involves plastic deformations on elastic metals. To improve the accuracy of the formed parts, the die surfaces are required to be optimized and compensate therefore after springback the geometry falls at the expected shape. The proposed procedure combined two methods of die compensation; Displacement Adjustment Method (DAM) and Spring‐forward method (SFM) of Karafillis and Boyce (K&B) called Hybrid Method (HM). Both are based on iteratively comparing the deformed shape with the target. According to the advantages of each method DA and K&B to solve the springback compensation problem, these methods are applied alternately. This paper presents and discusses the proposed framework in accommodating springback in sheet metal forming.

An accurate modelling of the sheet metal deformations including the springback prediction is one of the key factors in the efficient utilisation of Finite Element Method (FEM) process simulation in industrial application. Assuming that springback can be predicted accurately, there still remains the problem of how to use such results to appear at a suitable die design to produce a target part shape. It is this second step of springback compensation that is addressed in the current work. This paper presents an evaluation of a standard benchmark model defined as Benchmark II of Numisheet 2008, S-channel model with various drawbeads and blank holder force (BHF). The tool geometry modified based on springback calculation for a part to compensate springback. The result shows that the combination of the smooth bead with BHF of 650 kN resulted in the minimum springback and the tool compensation was successfully to accommodate the springback errors.