Department News
Interlaminar Deformation at a Hole in Laminated Composites :
Seminar Date
2000-10-19
Author
손문숙
Date
2000-10-19
Views
987
1. 제목 : Interlaminar Deformation at a Hole in Laminated Composites :
A Detailed Experimental Investigation Using Moiré Interferometry
2. 일시 : 2000년 8월 16일 (수) 14:00 – 15:00
3. 장소 : 301동 1512호
4. 연사 : Dr. DAVID H. MOLLENHAUER
Materials Research Engineer, Organic Matrix Composites
Air Force Research Laboratory, Materials and Manufacturing Directorate
5. Abstract:
The deformation along cylindrical surfaces of holes in tensile-loaded laminated composite specimens was measured using new moiré interferometry techniques. Two composite tensile specimens, fabricated from IM7/5250-4 prepreg with ply lay-ups of [04/904]3s and [+302/-302/904]3s, were examined using newly developed moiré interferometry techniques. Circumferential and thickness direction displacement fringe patterns, recorded in 3 0 segments around one quadrant of the hole periphery, were assembled into 90 0 wide mosaics for both composite specimens. Distributions of strain were calculated with high confidence on a sub-ply basis at select angular locations. Measured strain behavior was complex and displayed ply-by-ply trends. Large ply-related variations in the circumferential strain were observed at certain angular locations around the periphery of the hole in both composites. Extremely large ply-by-ply variations of the shear strain were also documented in both composites. Residual viscoelastic shearing strains were recorded in regions of large load-induced shearing strains. Large ply-group related variations in the thickness direction strain were observed in the [+302/-302/904]3s specimen. An important large-scale trend was observed in which the thickness direction strain tended to be more tensile near the outside faces of the laminate than near the mid-ply region. The measured strains were compared with a spline-based three-dimensional numerical technique, resulting in a very close match.
6. 연락처 : 기계항공공학부 이우일 교수 (전화 : 880-7116)
A Detailed Experimental Investigation Using Moiré Interferometry
2. 일시 : 2000년 8월 16일 (수) 14:00 – 15:00
3. 장소 : 301동 1512호
4. 연사 : Dr. DAVID H. MOLLENHAUER
Materials Research Engineer, Organic Matrix Composites
Air Force Research Laboratory, Materials and Manufacturing Directorate
5. Abstract:
The deformation along cylindrical surfaces of holes in tensile-loaded laminated composite specimens was measured using new moiré interferometry techniques. Two composite tensile specimens, fabricated from IM7/5250-4 prepreg with ply lay-ups of [04/904]3s and [+302/-302/904]3s, were examined using newly developed moiré interferometry techniques. Circumferential and thickness direction displacement fringe patterns, recorded in 3 0 segments around one quadrant of the hole periphery, were assembled into 90 0 wide mosaics for both composite specimens. Distributions of strain were calculated with high confidence on a sub-ply basis at select angular locations. Measured strain behavior was complex and displayed ply-by-ply trends. Large ply-related variations in the circumferential strain were observed at certain angular locations around the periphery of the hole in both composites. Extremely large ply-by-ply variations of the shear strain were also documented in both composites. Residual viscoelastic shearing strains were recorded in regions of large load-induced shearing strains. Large ply-group related variations in the thickness direction strain were observed in the [+302/-302/904]3s specimen. An important large-scale trend was observed in which the thickness direction strain tended to be more tensile near the outside faces of the laminate than near the mid-ply region. The measured strains were compared with a spline-based three-dimensional numerical technique, resulting in a very close match.
6. 연락처 : 기계항공공학부 이우일 교수 (전화 : 880-7116)
