| Project/Area Number |
08650106
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Materials/Mechanics of materials
|
|---|
| Research Institution | KYOTO UNIVERSITY |
|---|
Principal Investigator |
HOJO Masaki Kyoto University, Mesoscopic Materials Res.Ctr., Associate Professor, 工学部, 助教授 (70252492)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OCHIAI Shojiro Kyoto University, Mesoscopic Materials Res.Ctr., Professor, 工学部, 教授 (30111925)
|
|---|
| Project Period (FY) |
1996 – 1997
|
| Project Status |
Completed (Fiscal Year 1997)
|
| Budget Amount *help |
¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 1997: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1996: ¥1,700,000 (Direct Cost: ¥1,700,000)
|
|---|
| Keywords | Composite materials / Interlaminar fracture / Intralaminar fracture / Fatigue strength / Fracture toughness / Mesoscopic structure / Interface / Resin |
|---|
| Research Abstract |
Effects of interlaminar and intralaminar mesoscopic structures on the fracture toughness and fatigue crack growth resistance were investigated for CFRP laminates. In the present study, resin layrs at the prepreg interfaces and fiber/matrix interfacial strength were controlled. Comparison of interlaminar and intralaminar fracture properties was carried out to find out the role of resin rich layrs at the prepreg interface. A new type of heterogeneous resin for resin rich layrs which is composed of thermoplastic fine particles and epoxy of base lamina was also investigated. Finally, the effect of thickness and toughness of the resin rich layrs at the prepreg interface was separately analyzed, and the optimization of the resin rich layrs was discussed. The results are summarized as follows :
1.Mode II interlaminar properties of CFRP laminates with heterogeneous resin at prepreg interface
Fracture toughness and fatigue crack growth resistance were improved up to the level of CFRP laminates wi
… More
th tough thermoplastic resin. This high toughness was kept with the increment of crack growth.
2.Mode I and II interlaminar properties of thermoplastic resin interleaved CFRP
Polyethylene base thermoplastic resin was put at the prepreg interface of CFRP laminates. The mode I fracture toughness was almost the same as that for CFRP laminates with thermoplastic resin matrix. This high toughness was kept with the increment of crack growth. For the case of mode II,the toughness was more than 10kJ/m^2, which was much higher than that for CFRP laminates with thermoplastic resin matrix.
3.Effect of fiber/matrix interfacial strength on interlaminar and intralaminar fracture properties
The fracture toughness for mode I intralaminar tests increased with increasing surface treatment levels. The effect of the surface treatment on the fracture toughness for mode II interlaminar tests was smaller than that for mode I intralaminar tests. The fracture toughness for mode I interlaminar tests was insensitive to the surface treatment level for CF/epoxy laminates. The mesoscopic fracture mechanism was well correlated to the effect of the surface treatment on the basis of SEM observation. Less
|
