Predictability of Al-Mn Alloy Exposure Time Based on Its As-Cast Weight and Corrosion Rate in Sea Water Environment

Chukwuka Nwoye, Simeon Neife, Ebere Ameh, Awo Nwobasi, Ndubuisi Idenyi

Department of Industrial Physics, Ebonyi State University, Abakaliki, Nigeria.
Department of Metallurgical and Materials Engineering, Enugu State University of Science & Technology, Enugu, Nigeria.
Department of Metallurgical and Materials Engineering, Nnamdi Azikiwe University, Awka, Nigeria.
Department of Metallurgical and Materials Engineering, University of Nigeria, Nsukka, Nigeria.
Department of Technology and Vocational Education, Ebonyi State University, Abakiliki, Nigeria.

DOI: 10.4236/jmmce.2013.16046                

Abstract

This paper presents the predictability of aluminium-manganese alloy exposure time based on its as-cast weight and corrosion rate in sea water environment. The validity of the derived model: α = 26.67γ + 0.55β － 0.29 is rooted on the core expression: 0.0375α = γ + 0.0206β － 0.0109 where both sides of the expression are correspondingly approximately equal. Statistical analysis of model-predicted and experimentally evaluated exposure time for each value of as-cast weight and alloy corrosion rate considered shows a standard error of 0.0017% & 0.0044% and 0.0140% & 0.0150% respectively. The depths of corrosion penetration (at increasing corrosion rate: 0.0104 - 0.0157 mm/yr) as predicted by derived model and obtained from experiment are 0.7208 × 10^－4 & 1.0123 × 10^－4 mm and 2.5460 × 10^－4 & 1.8240 × 10^－4 mm (at decreasing corrosion rate: 0.0157 - 0.0062 mm/yr) respectively. Deviational analysis indicates that the maxi- mum deviation of the model-predicted alloy exposure time from the corresponding experimental value is less than 10%.

Keywords

Prediction; Exposure Time; Al-Mn Alloys; Sea Water; Alloy As-Cast Weight; Corrosion Rate

Conflicts of Interest

The authors declare no conflicts of interest.

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