This Research is aimed to predict the maximum varying blank holder force (VBHF) over the punch stroke in order to eliminate cracks on cup deep drawing product. The constant blank holder force during the process, it's frequently not capable to prevent cracking, effectively. Using the slab method with assuming a constant volume of material, the simple analytical approach of maximum VBHF, has been conducted under the failure deformation and cracking criteria on every stage punch stroke. The cracking criteria are based on the maximum strength of materials. Steel sheet of SPCD grade, thickness 0.2 mm was used in this study. And the diameter of the cylindrical cup-shaped product was 40 mm. The analytic calculation of the maximum VBHF has been compared to FEM simulations, and its effects in the prevention of cracking. Analytical Results of maximum VBHF, not much different with FEM simulation. Compared to the application of the constant blank holder force, VBHF can be quite effective for preventing the occurrence of cracking and increasing the formability of deep drawing.

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Due to the different properties of the materials, the fusion welding of dissimilar metals may be difficult. Structural irregularities may form as a result of various phase transformations during welding. Solid-state welding, as opposed to fusion welding, occurs below the melting temperature. As a result of the melting and solidification phenomena that happen in fusion welding, solid-state welding is expected to reduce the potential for phase transformation. This paper describes the use of a rotary friction welding technique to join carbon steel and 304 stainless steel. The purpose of this work is to investigate the characteristics of rotary friction welding (RFW) when joining 304 stainless steel to carbon steels with different carbon contents. Experiments were carried out on the RFW of low- and medium-carbon steels with 304 stainless steel. The investigation was carried out using the Taguchi method of experimental design. The joints’ tensile strengths and microstructures were evaluated. The parameters that had the greatest influence on the tensile strengths of the welding results were identified. The combination of parameters resulting in the greatest tensile strength is also suggested. A microstructural examination of the weldment revealed mechanical mixing and interlocking.

Drawbead are often used to control the flow of material, stress and deep drawing force in the flange area. This paper discussed the drawbead (fully, not fully and without drawbead) that combined with variations in the blank holder force against restriction of material flow and drawbead restriction force of deep drawing with palm oil lubrication. In this paper, analytical and experiments are used to predict the drawbead restraining and deep drawing force. The tin steel sheet with a thickness of 0.2 mm is used as speciment. The results obtained, that the application fully drawbead be very effective in controlling the flow of materials in the flange, as compared to not fully and without drawbead. In the beginning of the process (punch stroke < 4 mm), the magnitude of restraining force and deep drawing force can be increased. And, the magnitude of Radial Stress increases, conversely the magnitude of tangential stress decreased. This can prevent the occurrence optimum blank holder force is recommended in range 4394-8788 N. Comparisons of results between the analysis and experiments show the phenomenon is similar.