Predictability of Hardness of the Heat Affect Zone in Aluminum Weldments Cooled in Palm Oil Based on Hardness of Similarly Cooled Mild Steel and Cast Iron Weldments

Chukwuka Nwoye, Stanley Nwakpa, Agbo Alfred, Chidume Nwambu, Uche Obialor

Department of Mechanical Engineering, Abia Polythecnic Aba, 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.

DOI: 10.4236/jmmce.2013.16055                

Abstract

The predictability of hardness of the heat affected zone (HAZ) in aluminum weldments cooled in palm oil, based on hardness of similarly cooled mild steel and cast iron weldments has been ascertained. The general model: α = 1.2769  indicates that HAZ hardness of aluminium weldment is dependant on the ratio of product to sum of HAZ hardness of mild steel and cast iron weldments cooled in palm oil under the same conditions. The maximum deviations of the model-predicted HAZ hardness values α, μ and β from the corresponding experimental values α_exp, μ_exp and β_exp were less than 0.04% indicating the reliability and validity of the model.

Keywords

Model; Hardness; Heat Affected Zone; Aluminum Weldments; Mild Steel; Cast Iron

Conflicts of Interest

The authors declare no conflicts of interest.

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