Development of Novel Self-Healing for use in Wind Turbine Blades
Mentor 1
Ryo Amano
Location
Union Wisconsin Room
Start Date
24-4-2015 2:30 PM
End Date
24-4-2015 3:45 PM
Description
Wind turbine blades undergo fatigue and their performance depletes as time progresses due to the formation of internal cracks. Self-healing materials are a type of smart materials which have controlled ability to mend thermal and fatigue damages. Cracks in a material generally start off at a microscopic level, and subsequently propagate and connect together causing further damage. A structural material, after regular surface macroscopic maintenance, does not show the same performance standards as the virgin material due to the permanence of internal distortions. The ability to internally fill the crack delays failure of the material and allows prolonged high performance standards with low costs in future damage detection and maintenance. Self-healing in polymers is a unique characteristic used to heal the cracks inherently as they form. In this study, a new method is to be demonstrated for supplying the monomer (that is quintessential for the healing process) uniformly throughout a fiber reinforced polymer composite. The new method to be demonstrated is the use of 1 mm metal wires coated with release film. Each wire will be pulled out after the vacuum assisted resin transfer method (VARTM) and once the resin is completely cured. After pulling the wires out, a vascular network would be left to increase the accessibility of the healing agent. The creation of a vascular network has been attempted in past studies using commercial borosilicate tubing, but proved insufficient due to the microcracking being unable to penetrate the glass tubing. Manufacturing and testing of the wire samples will be systematically the same as the glass tubing samples: the wire layouts will be varied and their effect on the composite structure will be observed. Testing, such as Dynamic Mode Analysis (DMA), will be conducted on the samples to determine the mechanical properties. For making the polymer matrix composites, Volan finish glass fiber material was used. The molding procedure employed the VARTM process, which is an industry standard in manufacturing wind turbine blades. Six layers of glass fiber provided the required thickness for DMA testing. Commercial grade Marine epoxy resin and medium cure hardener were also used. The resin and the hardener were mixed in a 3:1 ratio by volume. Using a vacuum pump, a suction pressure of about 550 kPa was generated to infuse the resin into the glass fiber layers. The sample is then left to cure at room temperature for 24 hours. Once the sample is cured, it is ready to be cut and tested according to ASTM standards.
Development of Novel Self-Healing for use in Wind Turbine Blades
Union Wisconsin Room
Wind turbine blades undergo fatigue and their performance depletes as time progresses due to the formation of internal cracks. Self-healing materials are a type of smart materials which have controlled ability to mend thermal and fatigue damages. Cracks in a material generally start off at a microscopic level, and subsequently propagate and connect together causing further damage. A structural material, after regular surface macroscopic maintenance, does not show the same performance standards as the virgin material due to the permanence of internal distortions. The ability to internally fill the crack delays failure of the material and allows prolonged high performance standards with low costs in future damage detection and maintenance. Self-healing in polymers is a unique characteristic used to heal the cracks inherently as they form. In this study, a new method is to be demonstrated for supplying the monomer (that is quintessential for the healing process) uniformly throughout a fiber reinforced polymer composite. The new method to be demonstrated is the use of 1 mm metal wires coated with release film. Each wire will be pulled out after the vacuum assisted resin transfer method (VARTM) and once the resin is completely cured. After pulling the wires out, a vascular network would be left to increase the accessibility of the healing agent. The creation of a vascular network has been attempted in past studies using commercial borosilicate tubing, but proved insufficient due to the microcracking being unable to penetrate the glass tubing. Manufacturing and testing of the wire samples will be systematically the same as the glass tubing samples: the wire layouts will be varied and their effect on the composite structure will be observed. Testing, such as Dynamic Mode Analysis (DMA), will be conducted on the samples to determine the mechanical properties. For making the polymer matrix composites, Volan finish glass fiber material was used. The molding procedure employed the VARTM process, which is an industry standard in manufacturing wind turbine blades. Six layers of glass fiber provided the required thickness for DMA testing. Commercial grade Marine epoxy resin and medium cure hardener were also used. The resin and the hardener were mixed in a 3:1 ratio by volume. Using a vacuum pump, a suction pressure of about 550 kPa was generated to infuse the resin into the glass fiber layers. The sample is then left to cure at room temperature for 24 hours. Once the sample is cured, it is ready to be cut and tested according to ASTM standards.
