Light metals and alloys are highly fascinated by aircraft industries due to their good strength-to-weight ratio, which is the prime requirement for aviation’s designers. Assembling of aircrafts components is often carried out using tungsten inert gas (TIG) welding, which is more acceptable for heat treatable aluminum alloys. We focus on the viable use of TIG welded assemblies of 6061 aluminum alloys to homogenize its hardness properties by heat treatment. Investigation proceeds by perceiving the effect of different precipitation hardening conditions on Aluminum alloy through their micro and macro-structural behavior and microhardness analysis. The statistical examination was conducted to evaluate the integrity of heat treated samples. A new and efficient measure – the coefficient of reliability – is introduced to outline the best hardness preserving samples. The statistical analysis shows the effectiveness of the coefficient of reliability to outline the best samples. The experimental results show that the samples aged at 175oC for 12 hours preserve the hardness profile of the welded alloy. The result is also verified from the mean hardness, coefficient of reliability and standard deviation values and in agreement with literature.
6061-Al-alloy,Tungsten inert gas welding (TIG),Precipitation hardening,Micro and macro structures,Microhardness,Statistical analysis,
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