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Bipolar plates are the most important of fuel cells components. These plates are made with different methods such as machining, molding and forming and they are made of variety materials such as graphite, composite and metal plates. In this research, forming of metallic bipolar plates with pin-type pattern from stainless steel 304 with 0.11mm thickness is investigated numerically and experimentally using hydroforming process in convex die. In this regard, several parameters such as applied pressure, pin geometry, and depth to width ratio of the profiles has been changed and the experimental and simulation results of formed profiles, filling percent, thickness distribution and thinning percent of the formed parts have been compared. The results have been shown that no safe sample has been reached in depth to width ratio 1, while safe samples have been formed in depth to width ratio 0.67 in circle (a/b=1) and ellipse (a/b=0.7) samples and all samples in depth to width ratio 0.33 at 300 MPa pressure level in viewpoint of filling and thinning percentage. In general, increasing the small diameter to big diameter ratio (a/b) and decreasing the depth to width ratio (h/w) makes the thinning percent and filling percent more desirable.

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In recent years the use of metallic bipolar plates for fuel cells is considered. Several studies have been conducted on the various methods of forming these plates. Most of this research has been done on the serpentine flow fields. While in some cases that the pressure drop is important factor, the pin-type flow fields shows good performance. In this research, hydroforming of metallic bipolar plates with circular pin-type pattern from stainless steel 304 with 0.11mm thickness is investigated experimentally and numerically. For this purpose, the effect of geometrical parameters such as the die wall angle, the die chamfer dimension, the depth-to-width ratio of the die, and forming pressure on the profiles, filling percent, thickness distribution and thinning percent of the formed parts are investigated. In this regard, two dies with wall angle of 0 and 15 degree were prepared. Then experimental tests were done at different pressures. After performing the required tests, the results show that the die wall angle leads to a more uniform thickness distribution and higher precision of the parts profile. Also the suitable range of die geometrical parameters was determined.

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Few studies have explored the relationship between non-cognitive factors in different educational settings and with different age groups. The purpose of this study is to determine whether there is a relationship between Study Habits (SH) and Commitment to Ethical Codes (CEC) and their ability to predict the academic performance of language learners in schools and universities (547 students aged under 18 – above 35 years old). The instruments used are adapted versions of questionnaires which were made into one survey tool with each measure in distinct sections. The results showed a significant relationship between SH and CEC displaying a positive relationship in all age groups (a highest relationship in the age group of 18-22, P< 0.05) and in both male/females with male participants reported having the highest relationship (P< 0.05). The study concludes that CEC needs to be considered and assessed during school years with additional training to language learners to help them learn or modify SH to increase their performance at the time of entry into university.