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Copyright of Journal of Donghua University (Natural Science Edition) is the property of Journal of Donghua University (Natural Science) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the anti-penetration property of carbon fiber composite materials, a series of experiments need to be carried out. In experiments, 8 g cubic steel fragments penetrated carbon fiber reinforced plastics whose thickness are 5, 10 and 15 mm respectively. The velocity of fragments was obtained, the situation of target was observed, fragments and carbon fiber were recovered. The numerical simulations were carried out according to the situation of experiments. The process of fragments penetrating carbon fiber composite target was explored, and the failure mechanism of carbon fiber composite target was also explored. The relationship between the failure mode and velocity of fragments could be described as follows: when the fragment velocity exceeds the ballistic limit, the main form of target damage is fiber shear failure; when the fragment velocity is lower than the ballistic limit, the damage forms of the target include fiber shear failure, fiber tensile failure, matrix cracking and fiber layer delamination, and their proportions change with the fragment velocity. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the impact resistance and dynamic damage rule of reinforced concrete (RC) beams strengthened with carbon fiber reinforced plastics (CFRP) under different impact velocities, four CFRP strengthened RC beams were tested by using a drop-hammer impact device. The analysis results of the failure pattern, crack propagation rule, dynamic time history response and energy dissipation of the strengthened beams show that with increase of the impact velocity, the width of the main bending crack in the mid-span of CFRP strengthened beam increases first and then decreases, and the width of the main oblique crack in the mid-span increases continuously. It can also be identified that overall crack distribution converges to the mid-span area. Furthermore, the peak impact force and the mid-span peak displacement are linearly dependent to the impact velocity. The energy dissipation capacity of strengthened beams increases nonlinearly with the increase of impact velocity. The greater the impact velocity is, the less the increase rate of the energy dissipation capacity of the strengthened beam is. In addition, four stages can be divided in the test based on development of mid-span displacement, which are linear growing, nonlinear growing, rebounding and stable stages, respectively. The study can provide reference for optimal design of RC beams strengthened with CFRP. [ABSTRACT FROM AUTHOR]

Copyright of China Synthetic Fiber Industry is the property of Sinopec Baling Petrochemical Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carbon fiber reinforced plastics (CFRP) has broad application prospects in aerospace, national defense, and other fields due to its excellent performance. In order to master the removal mechanism of laser processing CFRP, and to developed a high efficiency, low damage processing method of the material, the researches of the removal mechanism of CFRP by laser processing were reviewed. The progress of laser processing CFRP materials at domestic and abroad was introduced from the aspects of laser characteristics, process parameters, gas-liquid assistance and material properties. The factors affecting the quality of laser processing CFRP were summarized. Some suggestions to improving the processing quality were proposed. Finally, the development trend of laser processing CFRP was prospected. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced plastics ( CFRP) is prone to defects such as uneven heat-affected zone and fiber damage during the laser surface ablation and epoxy removal process. In order to solve this problem, a laser stripping process algorithm based on CFRP fiber woven grid block scanning was proposed and implemented. Theoretical analysis and experimental verification were carried out by single-factor experiment method, and the influence of different laser scanning surface fiiling algorithms on the resin removal rate and fiber damage degree of CFRP surface were obtained. The laser ablation mechanism was also analyzed and studied. The result shows that the processed samples have better process effects such as fiber integrity and less thermal damage undertheconditions ofaverage power 24W, repetition rate 20kHz, scanning speed 1000mm/s, defocus length 5mm, which is helpful for the research of CFRP laser resin removal. [ABSTRACT FROM AUTHOR]

In order to reveal the distribution of temperature field, the absorption and transfer of energy, and the formation mechanism of heat affected zone during laser cutting carbon fiber reinforced plastics, the carbon fiber reinforced plastics was chosen as the research object, and the multiphysics model of laser cutting carbon fiber reinforced plastics was established. The temperature field distribution during laser cutting and the influence of laser parameters on carbon fiber reinforced plastics temperature and heat affected zone were calculated. The 3-D temperature field distribution during laser cutting carbon fiber reinforced plastics was then obtained. The results show that the surface temperature field of carbon fiber reinforced plastics is approximately elliptical during laser cutting. The energy transfer and diffusion in carbon fiber reinforced plastics are mainly along the direction of carbon fiber laying. When the laser power is 20W, the spot radius is 100µm, and the laser with a cutting speed of 50mm/s is cut perpendicular to the carbon fiber laying direction, the carbon fiber temperature at the laser spot is much lower than the temperature of the resin layer. With the increase of spot radius and laser power, the maximum temperature in carbon fiber reinforced plastics increases gradually, and the heat affected zone gradually increases. With the increase of cutting speed, the maximum temperature in carbon fiber reinforced plastics gradually decreases, and the heat affected zone gradually becomes smaller. This study provides theoretical guidance for understanding the thermal damage mechanism of laser cutting carbon fiber reinforced plastics and the high quality and efficient processing of materials. [ABSTRACT FROM AUTHOR]

Bonding capacity of the interface between FRP plate and concrete can be evaluated by FRP-concrete interface slippage curve. In order to find a relatively accurate interface bond-slip model, the interface performance of concrete beam strengthened with externally bonded CFRP plate was studied. Strengthened wide-notch concrete beam models were fabricated and tested, where the concrete cover at the pure bending section of models was partly removed to form the wide-notch on the side surface, externally bonded CFRP plates were used to strengthen the beams and the four-point bending test was accomplished. External measuring devices were mounted on the beam models to accurately measure the slippage of certain beam sections along the beam span. Results show that the test and its testing system are suitable to study the bonding shear stress and the slip properties at the interface of concrete and CFRP plate. The designated beam section movement is easy to measure. The stress distribution is clear and the average shear stress of CFRP plate is convenient to obtain. The slippage and bond-slip curve are accurate. Strain gauges are not necessary for the measurement of slippage. Thus the testing system and calculation method for slippage reported in this paper can provide help with other researches on the interface properties of CFRP and concrete. [ABSTRACT FROM AUTHOR]

During the process of drilling carbon fiber reinforced plastics (CFRP), it tends to effectively reduce or eliminate manufacturing deficiency, such as burr and delamination using electroplated diamond step-core drill whose service life mainly depends on the service life of electroplated diamond abrasive. Therefore, systematic statistical observation was carried Out on the abrasive wear patterns of electroplated diamond. Investigations show that using the electroplated diamond step-core drill, three unique stages of diamond abrasive wear can be observed during the process of drilling T300 CFRP, which involves initial instable wear stage, mixed-wear stage and normal wear stage. The wear patterns of diamond abrasive and drilling thrust force have a significant linear relationship. With the growing of hole numbers, the thrust force gradually increases, but diameter tolerances of the holes are still stabilized in a range of 0. 024 mm after the initial instable wear stage. [ABSTRACT FROM AUTHOR]