In this paper, the mechanical erosion effect during continuous-wave (CW) laser ablation of GFRP (Glass Fiber Reinforced Polymer) was studied. It happened under the condition of subsonic tangential airflow. In order to know the effect of mechanical erosion in the ablation process. An experimental device was designed to collect mechanical erosion products. The total mass loss of GFRP in the process of laser ablation and mass loss caused by mechanical erosion were measured by experiments. Then the percentage of mechanical erosion was calculated. The experiments were made at different airflow velocities and different laser power densities. Spot center temperature was measured during the experiment. The results show that the percentage of mass loss caused by mechanical erosion will increase and tend to be constant with the increase of airflow velocity. The percentage of mass loss caused by mechanical erosion will increase with the increase of laser power density. The percentage of mass loss caused by mechanical erosion will increase and tend to be constant with the increase of laser irradiation time. The mechanical erosion effect of GFRP is related to its laminated structure. The laminated structure can affect the mechanical erosion mechanism of the material surface. It will cause the regular change of the surface temperature of the material.
The irradiation effects are studied, of continuous wave (CW) laser on five types of laminated carbon fiber composites (CFRP), [0/90/0/90], [0/90/90/0], [0/45/90/135], 1.5K-Textile ([1.5K/0°/90°/1.5K]) and 3K-Textile ([3K/0°/3K]). The ply scheme of CFRP is especially considered in the proposed 3D model. The numeirical results show that the structure of CFRP has significant influences on the temperature evolution and the heat affect zone (HAZ). The non-monotonic temperature rising at the material surface exposed to the laser radiation are associated with the heat flux in the laminated structure. The HAZ in the adjacent layers is discontinuous. The pyrolysis inside the CFRP is more serious than the one on the laser irradiation surface. The numerical predictions indicate that the material with [0/45/90/135] has the optimum thermal insulation performance. This kind of ply scheme could promote lateral heat transfer and weaken longitudinal heat transfer. 3K-Textile has optimal ablation resistance. It is associated with the 3K-Textile layer having the maximum longitudinal thermal conductivity.
A multiscale approach is used to analyze the oxidation ablation of parallel carbon fiber (the fibers are parallel to the material surface) reinforced polymer composites(CFRP). The matrix and fiber will be eroded at extreme temperatures. Because the ablation rate of matrix is bigger than fiber, the fiber will be exposed in a certain depth from surface. In the microscale, a model is developed for analyzing the number of exposed fibers and the fiber geometry at low air flow and different temperatures. The model shows that the exposed number increases with the growth of ratio of ablation rate of matrix and fiber, and the ratio doesn’t monotonously increase with the rise of temperature. Surface ablation gradually turns to volume ablation with the increase of the number of exposed fibers. In the macroscale, the effective reactivity of the material is equal to the integral over the ablation zone. Compared with perpendicular carbon fiber reinforced polymer composites, both of them reach maximum number or length of exposed fibers during the transition temperature region where "reactivity limit" turns to "diffusion limit". When the fibers are perpendicular to the surface, the macro ablation behavior agrees with “weakest link law”, in other words the matrix recession rate is the most determining parameter for the effective behavior, but it may be not reasonable for parallel fibers.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.