Evaluation on the Mechanical and Corrosion Resistance of ALDC 12 Al Alloy by Three Types of Heat Treatments

Abstract:

Al is a active metal. However, it has a generally fine oxide film with thin and protective barrier, which is stable in air and neutral aqueous solution. Thus, Al alloys have been widely used in architectural trim, cold & hot-water storage vessels and piping. However, Al and most of their alloys may be easy to be corroded with various patterns of corrosion such as pitting, intergranular and galvanic corrosion etc. in the case of exposure to various industrial and marine corrosive environments. Therefore, an optimum evaluation of corrosion resistance for Al and Al alloys may be more important in a economical point of view. In this study, characteristics evaluation for ALDC 12 Al alloy by solution, normalizing, and aging (natural and artificial) heat treatments was carried out using electrochemical methods etc.. We can see that the hardness of ALDC 12 Al alloy were decreased by solution and aging heat treatments, in particular, the solution and natural aging (SNA) heat treatments indicated the lowest value of hardness. However, the lower hardness by heat treatment, the better corrosion resistance, for instance, the solution and natural aging (SNA) heat treatment exhibited the best corrosion resistance with showing the lowest hardness. Furthermore, the highest hardness was observed after normalizing and artificial aging (NAA) heat treatments. Therefore, it is considered that if improvement of the hardness as well as the corrosion resistance were to be required together, the normalizing and artificial aging (NAA) heat treatment should be performed. On the other hand, the solution and natural aging (SNA) heat treatment is thought to be an optimum heat treatment method for only corrosion resistance improvement.

• Periodical: Key Engineering Materials (Volume 744)
• Pages: 249-253
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.744.249
• Online since: July 2017
• Authors: Kyung Man Moon, Sung Yul Lee, Jae Hyun Jeong*, Myeong Hoon Lee
• Keywords: Aging, Corrosion Resistance, Hardness, Inter Granular Corrosion, Normalizing, Solution Treatment

References

[1] H. Y. Lee, Metal Corrosion Engineering. Y. K. Munhwa. Pub. (1999) 262.

[2] S. K. Suriyama, Non metal material Engineering. Korona. Pub. (1975) 142.

[3] G. M. Fontana, Corrosion Engineering, Mc Graw Hill Book company. (1986) 516.

[4] D. A. Jones, Principles and Prevention of Corrosion. Prentice Hall International, Jnc. (1996) 618.

[5] J. W. Martin, Precipation Hardening. Oxford Pergamon. (1968) 345.

[6] Y. Murakami, Fundamentals and Industrial Technologies of Aluminum Materials. Japan Light Metals Association. (1985) 252.

[7] Y. Murakami, Advanced Materials and Technology. Proc. 2nd Int. Conf. Kobe, Japan. (1991) 113.

[8] A. Hellawell, supplementary Volume 2 of the Encyclopedia of Material Science and Engineering, Oxford Pergamon. (1990) 115.

[9] H. W. L Phillips, Annotated Equilibrium Diagram of Some Aluminum Alloy Systems, Monograph No. 35 London Int. Metals. (1959) 57.

[10] A. Sakamoto, Advanced Materials and Technology. New Composites, Proc. 2nd Int. Conf. Hyogo, Japan. (1991) 165.

[11] E. A. Starke, Materials Science, Seminar, Proc. ASM. (1979) 208.

[12] J. Gilbert, K. Elwin and L. Rooy, ASM international Materials Park, OH 44073-002. (1965) 61.

[13] S. K. Suriyama, Non metal material Engineering. Korona. Pub. (1975) 152, 159.

[14] N. J. Beak, Metal Material Engineering, K. L. Pub. (1983) 260.