Journal of Modern Processes in Manufacturing and Production
Year:2010 | Volume:1 | Issue:2|Papers Count:9

New requirements of the automotive industry, concerning lightweight and non-corroding construction, demand new production methods. Thus the hydroforming process of aluminum and Magnesium alloys are of special interest. Main drawback of these alloys is low formability in room temperature that can enhanced with increasing the temperature. In this paper, tube hydroforming of AA3003 alloy in various temperatures was investigated numerically. MSC. Marc software was used for simulation and thickness distribution in forming zone was studied in various temperatures.Results in different axial load conditions were compared.

Friction stir processing is a solid state process to modify microstructure and mechanical properties of sheet metals and as-cast materials. In this process stirring action of the tool causes the material to intense plastic deformation that yields a dynamical recrystallization. In this study the effect of FSP and process parameters on hardness, and microstructure of Al5083 has been investigated. Also by using of FSP, composite layer of TiO2/Al5083 has been produced. Results show that, FSP leads to finer and homogenized grain structure, as well as increased hardness, strength, toughness, and elongation of material. The composites produced by FSP have uniformly distribution of TiO2 particles between the grains of base metal.

Gearbox is a main component of rotating machines. Any fault in gearboxes not detected and removed on time, results in stopping the system or damaging it. So, early detection of faults is of critical importance. Here, in order to automatic detection of gear faults based on Acoustic emission signals Logistic Model Tree (LMT) classification method is applied. Wavelet transform is used to analyse Acoustic Emission signals recorded from a defected gear. Then, some discriminative features are extracted from different frequency bands. From many different extracted features, the most relevant ones are selected using feature selection algorithms. At last, a Logistic Model Tree is used to classify the undefected and defected gears; also, the types of defects are recognized. Undefected and defected gears are discriminated with 99% of accuracy and types of defects are correctly identified with the rate of 80%.

Currently, double layer sheet rolling is classified as asymmetric rolling process. Friction coefficient, angle velocity rate and stress strength ratio are effective factors in this process. Forced rolling significantly reduced by increasing velocity rate of two roles. Distribution of plastic strain is not equal due to disequilibrium of material mechanical characteristics through the sheet thickness. So, material performance is similar to plain strain and it bends at discharge point. The flow stress of weaker layer is bigger than the stronger layer so sheet tends to bend toward the stronger layer. sheet curvature at exited zone can be regulated by angle velocity ratio and friction coefficient control. Shear strain and axial strain (in discharge) at the location of sheets junction is the most important factor which known to form the radius curvature of low strength stress.

Alluminum Alloys have important applications in recent years. In this paper we discuss explosive forming of aluminum alloy plates and effects of different parameters such as thickness, radius of mold, so as to monitor the effects of these parameters on velocity, deformation and stress. what we gain matches with existing valid results to an acceptable level.

In this work, the influence of different EDM parameters (current, pulse on-time, pulse off-time, arc voltage) in finishing stage on the material removal rate as a result of application copper electrode to a work piece (cold work steel DIN1.2379) has been investigated. Design of the experiments was chosen full factorial and statistical analysis was used for analysis of experimental data in this study. Finally, to select the optimal machining conditions presented a mathematical model to achieve suitable material removal rate.

In this paper, Vacuum Assisted Resin Transfer Molding (VARTM) Method simulated by analytical solution. Then the effect of parameters like fiber density, distribution of layer thickness, perform layer thickness, resin viscosity was investigated theoretically. Obtained results show that by selecting optimum distribution layer thickness, increasing fiber volume fraction, reducing viscosity of resin, maximum speed could be achieved in the process in such a way by optimizing these parameters the production speed will be improved.

One of the bellows producing method is hydroforming process. Whereas some factor of hydroforming process specially internal pressure effects on final characteristics produced bellows such as bursting, wrinkling and wall thickness distribution. in this paper the effect of internal pressure factor in final quality of produced bellows will be investigated.In simulation of process, ABAQUS/Explicit version 6.9 code was used, and also experimental examinations for investigation the effect of this factor has done.The results obtained from methods of analytical, finite element and experimental in this paper has good agreement with each other.Also, the conclusions of this research for prediction of suitable forming pressure could be used as a basis of designing a new type of metal bellows.

The use of TWB has been developed in automotive industries because of it’s advantages such as reduction in weight, cost and fuel economy of vehicles. The main objective of the peresent work is to study the effects of weld zone, diffrence in surface coating and thickness ratio on the formability of TWB composed of AISI 304, SPCC and IF steel sheets. It was found that the narrow weld zone has little effect on the formability of TWB. Results of LDH testing of TWB reveals the formability of TWB decrease as the thickness ratio of sheet increases. Fracture in LDH testing of TWB that composed of steel sheets with different surface coating occured on uncoated sheet because of changing in surface friction conditions.