Hybrid superplastic forming of AZ31B magnesium alloys
Sze, Swai Ming
Date of Issue2015
School of Mechanical and Aerospace Engineering
Superplastic forming has been a useful process applied in the manufacture of complex components in the automotive and aerospace industries with high degree of precision. However, this technology requires expensive materials with fine grain sizes and high temperature conditions with slow forming rates. A hybrid forming technique has been designed with the combination of deep drawing (hot drawing) followed by superplastic forming to achieve a faster forming speed. This report would investigate the formability of non-superplastic grade magnesium alloy AZ31B through series of tensile tests under controlled temperatures and strain rates. Additionally, tests of the new hybrid superplastic forming was also conducted using non-superplastic grade AZ31B blanks. The tensile test results show that strain rates of 1E-3 or above will limit the effects of temperature on ductility. It is likely that high strain rates hinder the recrystallization process. Hybrid superplastic forming technique combines the mechanical preforming process with superplastic forming, creating a hybrid process that forms a component faster while retaining the advantages of superplastic forming to form complex parts. A component can be formed in about 30 minutes. Thickness profiling of the components were done to understand its formability microstructural study was also performed to identify the effects of hybrid superplastic forming on the material.
Final Year Project (FYP)
Nanyang Technological University