Static and dynamic deformation behavior of combined geometry AISI 304L stainless stell shells
Başlık:
Static and dynamic deformation behavior of combined geometry AISI 304L stainless stell shells
Yazar:
Şahin, Selim, author
Yazar Ek Girişi:
Fiziksel Tanımlama:
xiii, 114 leaves: color illustraltions.+ 1 computer laser optical disc.
Özet:
In this study, the static and dynamic crushing behavior of combined geometry shells consisting of hemi-spherical and cylindrical segments were studied both experimentally and numerically. The proposed geometries were manufactured by deep drawing. Due to the nature of the deep drawing process, specimens inherited significant amount of residual stress/strain and thickness variation along the cross-section was observed. Thus, the manufacturing process was also numerically modeled explicitly. Quasi-static compression and dynamic drop weight tests were conducted both experimentally and numerically. The plastic deformation of the combined geometry shells started with the inward dimpling of the hemi-spherical segment and progressively continued deforming with the asymmetric or axisymmetric folding in cylindrical segment depending on the radius to thickness ratios and strain rates. The failure/fracture was observed in the thicker specimens at dynamic strain rates and that caused decreases in specific absorbing energy (SAE) levels. In addition, the energy partitions between the hemi-spherical segments increased at higher loading rates. Furthermore, the inertia and rate sensitivity influenced the crushing response of cylindrical segment more than that of hemi-spherical segment and inertia effect was more pronounced than the rate sensitivity at higher loading rates. Considering the thermal effects in the crushing behavior of the combined geometry shells, it was shown that the mean crushing load lowered as the temperature increased. Additionally, the percentages of increase in the crushing load were limited at lower temperatures for varying loading rates. It was shown that as the absolute temperature increased the percentage of increase in crushing load was significantly increased due to the change in deformation mode.
Konu Başlığı:
Yazar Ek Girişi:
Tüzel Kişi Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Master)--İzmir Institute of Technology: Mechanical Engineering.
İzmir Institute of Technology: Mechanical Engineering--Thesis (Master).
Elektronik Erişim:
Access to Electronic Versiyon.