INFLUENCE OF CORROSION ON MECHANICAL PROPERTIES AND MICROSTRUCTURE OF 3XXX, 5XXX, AND 6XXX SERIES ALUMINUM ALLOYS

Growing demands imposed on passenger car producers concerning the reduction of exhaust emission to the environment are forcing a search for new materials and design solutions. One of the most-important factors that can reduce this emission is the low mass of a vehicle, leading to a decrease in its average fuel consumption. A reduction in weight can be obtained by the use of aluminum elements instead of steel; e.g., in air conditioning pipes, decreasing the specific weight of the construction by nearly three times. In the present study, the influence of the SWAAT corrosion test on A/C piping made from 3xxx, 5xxx, and 6xxx series aluminum alloys was investigated. The study focused on changes in the mechanical properties of samples before and after a SWAAT test determined by a tensile test and Vickers hardness measurements. Additionally, microstructure examinations were performed with the use of optical and scanning microscopy. Corrosion products on the surface of pipes were identified by Energy Dispersive X-ray Spectroscopy. Pipes made from the EN AW 6063 alloy revealed an almost 50% decrease in its strength properties after the tests. The largest decline in plastic properties was observed in pipes made from the EN AW 6060 alloy

Prime Factorization of Sums and Differences of Two Like Powers

Representation of a non zero integer as a signed product of primes is unique similarly to its representations in various types of positional notations [4], [3]. The study focuses on counting the prime factors of integers in the form of sums or differences of two equal powers (thus being represented by 1 and a series of zeroes in respective digital bases).Although the introduced theorems are not particularly important, they provide a couple of shortcuts useful for integer factorization, which could serve in further development of Mizar projects [2]. This could be regarded as one of the important benefits of proof formalization [9].Department of Carbohydrate Technology University of Agriculture Krakow, PolandGrzegorz Bancerek. The fundamental properties of natural numbers. Formalized Mathematics, 1(1):41-46, 1990.Grzegorz Bancerek, Czesław Bylinski, Adam Grabowski, Artur Korniłowicz, Roman Matuszewski, Adam Naumowicz, Karol Pak, and Josef Urban. Mizar: State-of-the-art and beyond. In Manfred Kerber, Jacques Carette, Cezary Kaliszyk, Florian Rabe, and Volker Sorge, editors, Intelligent Computer Mathematics, volume 9150 of Lecture Notes in Computer Science, pages 261-279. Springer International Publishing, 2015. ISBN 978-3-319-20614-1.Paul Erdős and János Surányi. Topics in the Theory of Numbers, chapter Divisibility, the Fundamental Theorem of Number Theory, pages 1-37. Springer New York, 2003.Jacek Gancarzewicz. Arytmetyka, 2000. In Polish.Andrzej Kondracki. The Chinese Remainder Theorem. Formalized Mathematics, 6(4): 573-577, 1997.Artur Korniłowicz and Piotr Rudnicki. Fundamental Theorem of Arithmetic. Formalized Mathematics, 12(2):179-186, 2004.Rafał Kwiatek. Factorial and Newton coefficients. Formalized Mathematics, 1(5):887-890, 1990.Rafał Kwiatek and Grzegorz Zwara. The divisibility of integers and integer relatively primes. Formalized Mathematics, 1(5):829-832, 1990.Adam Naumowicz. An example of formalizing recent mathematical results in Mizar. Journal of Applied Logic, 4(4):396-413, 2006.Akira Nishino and Yasunari Shidama. The Maclaurin expansions. Formalized Mathematics, 13(3):421-425, 2005.Konrad Raczkowski and Andrzej Nedzusiak. Real exponents and logarithms. Formalized Mathematics, 2(2):213-216, 1991.Marco Riccardi. Pocklington’s theorem and Bertrand’s postulate. Formalized Mathematics, 14(2):47-52, 2006.Piotr Rudnicki and Andrzej Trybulec. Abian’s fixed point theorem. Formalized Mathematics, 6(3):335-338, 1997.Rafał Ziobro. Fermat’s Little Theorem via divisibility of Newton’s binomial. Formalized Mathematics, 23(3):215-229, 2015