Akademik Veri Yönetim Sistemi
9th International Azerbaijan Congress on Life, Engineering, Mathematical, and Applied Sciences, Baku, Azerbaycan, 20 - 22 Aralık 2024, ss.1-2
In this study, AA2024 powders were
placed into a sintering mold at specified weights and produced using powder
metallurgy, followed by thixoforging as a post-processing method. Due to the
significant limitation of powder metallurgy - typically resulting in low
density and thereby reduced mechanical properties - the powders were compressed
at 208 MPa using cold hydraulic pressing. Subsequently, the samples underwent
hot solid-state sintering at 500°C for approximately 90 minutes. To further
enhance density and mechanical properties, thixoforging was applied
post-sintering. Specimens were reheated to 615°C for 45 minutes, then
thixoforged in an open die with a 50% plastic deformation rate, and air-cooled.
Upon microstructural examination, a heterogeneous structure of large and small
grains was observed. The reheating before forging led to partial melting of
alloying elements, which concentrated around the α-Al phase, rounding off the
microstructural edges and reducing porosity. Density was measured using Archimedes'
Principle, while hardness and tensile strength were evaluated across the
cross-section. An increase in density from 97,516% to 99,346% was recorded.
Furthermore, by averaging the hardness measurements taken across the
cross-section, an improvement from 96 HB to 127 HB was observed, representing
an approximate 33% increase. Similarly, tensile strength values showed an
increase from 220 MPa to 312 MPa, achieving around a 42% enhancement.