New Rolled Aluminium Alloy Products for the Automotive Industry

Abstract

Clad aluminium strips are used in the automotive industry to manufacture parts of heat exchangers. They are characterised by favourable strength properties, good corrosion resistance and susceptibility to plastic deformation, and can undergo surface brazing at a temperature of about 600• C. As a result of studies, the properties of alloys for the production of clad strips have been optimised. Optimising covered the alloy chemical composition and selected parameters such as the metal condition, the mechanical properties and anti-corrosion behaviour, including the methods for corrosion potential equalisation and sacrificial protection. The obtained technological results of the clad aluminium strip production were verified under the industrial conditions of Impexmetal Huta Aluminium Konin S.A. In a laboratory of the Institute of Non-Ferrous Metals (IMN), the clad strips were tested for the pre-assumed functional properties. Mechanical properties were tested, and the structure and corrosion behaviour were characterised. The reactivity of the clad layer was analysed under different technological conditions. The thermal bond produced by these clad layers was tested by simulation of the heat exchanger manufacturing process. As a result of the conducted research it has been found that all the essential characteristics of the clad strips produced under domestic conditions are in no way different from the properties of imported strips, while modification of the alloy chemical composition has contributed to the effective sacrificial protection of heat exchangers made from these strips. Clad aluminium strips are now successfully produced by the domestic aluminium industry. The improvement of materials used for the heat exchangers can contribute to the reduced overall dimensions of these products and increased efficiency, thus leading to energy savings. The results were obtained within the framework of the Task No. ZPB/38/66716/IT2/10 executed as part of the "IniTech" Project.Keywords: aluminium alloys, clad aluminium strips, brazing, corrosion resistance, automotive industry Aluminiowe taśmy platerowane znajdują zastosowanie w przemyśle motoryzacyjnym do produkcji elementów wymienników ciepła. Charakteryzują się one korzystnymi właściwościami wytrzymałościowymi, dobrą odpornością na korozję i podatnością do odkształcenia plastycznego oraz zdolnością do zgrzewania powierzchniowego w temperaturze około 600• C. W wyniku badań dokonano optymalizacji właściwości stopów przeznaczonych do produkcji taśm platerowanych. Zoptymalizowano skład chemiczny stopów oraz wybrane parametry takie jak stan materiału, właściwości mechaniczne i antykorozyjne z uwzględ-nieniem metody wyrównania potencjałów korozyjnych oraz metody ochrony protektorowej. Efekty technologii platerowanych taśm aluminiowych zostały pozytywnie zweryfikowane w warunkach przemysłowych Impexmetal S.A. Huta Aluminium Konin. W warunkach laboratoryjnych IMN przetestowano wytworzone taśmy pod kątem założonych własności użytkowych. Zbadano własności mechaniczne taśm, scharakte...

The influence of sodium chlorides fog on corrosion resistance of heat exchangers used in automotive

“…The most important are: tightness, mechanical durability, heat production and corrosion resistance which is particularly important for products that operate in chemically aggressive environments which cause the transformation of the metal to oxide, salt or other compound resulting in deterioration of its functionality [1][2][3][4][5]. The main environmental factors which impact on the intensity of phenomenon of heat exchange corrosion are: car exhaust and other pollution, sodium chloride compounds, temperature and humidity [6][7][8][9].…”

The measurements of temperature and deformations of car radiators

“…The limited possibility of deformation of construction results in the appearance of sectional heat strains usually caused by uneven distribution of temperature in radiator, inhomogeneity of mechanical properties, chemical composition and the metallographic structure of materials, especially brazed joints. The continuous activity of heat loads results in the thermal fatigue of radiator characterized by the net of cracks on its surface [5][6][7][8][9][10][11].…”