A team of researchers from the Duke Soft Active Materials Laboratory has observed, for the first time, the creasing to cratering instability in polymers under electrical voltages. When bread dough is raised in a bowl, the top surface of the dough may fold upon itself to form creases due to compressive stresses developed in the dough. Surprisingly, this phenomenon may be related to failures of electrical polymers that are widely used in energy-related applications. Subjected to a voltage, a substrate-bonded polymer film develops a biaxial compressive stress parallel to the film. When the voltage reaches a critical value, the compressive stress induces a pattern of creases on the polymer. If the voltage further rises, the creases strikingly evolve into craters in the polymer, as the electrical stress pulls the creases open. Polymers usually breakdown electrically immediately after the creasing instability, which can cause failures of insulating cables and organic capacitors. The Duke team innovatively introduces a protective layer right beneath the polymer film. The protective layer prevents the electrical breakdown, but allows the team to observe the creasing to cratering instability. If you have any questions, please contact qiming.wang@duke.edu.
Creasing to Cratering under Voltages
Posted Saturday, September 8, 2012 in Cratering, Creasing, HandsOn, Samsung, Voltages by Unknown
Creasing to Cratering under Voltages Video Clips. Duration : 0.68 Mins.
A team of researchers from the Duke Soft Active Materials Laboratory has observed, for the first time, the creasing to cratering instability in polymers under electrical voltages. When bread dough is raised in a bowl, the top surface of the dough may fold upon itself to form creases due to compressive stresses developed in the dough. Surprisingly, this phenomenon may be related to failures of electrical polymers that are widely used in energy-related applications. Subjected to a voltage, a substrate-bonded polymer film develops a biaxial compressive stress parallel to the film. When the voltage reaches a critical value, the compressive stress induces a pattern of creases on the polymer. If the voltage further rises, the creases strikingly evolve into craters in the polymer, as the electrical stress pulls the creases open. Polymers usually breakdown electrically immediately after the creasing instability, which can cause failures of insulating cables and organic capacitors. The Duke team innovatively introduces a protective layer right beneath the polymer film. The protective layer prevents the electrical breakdown, but allows the team to observe the creasing to cratering instability. If you have any questions, please contact qiming.wang@duke.edu.
A team of researchers from the Duke Soft Active Materials Laboratory has observed, for the first time, the creasing to cratering instability in polymers under electrical voltages. When bread dough is raised in a bowl, the top surface of the dough may fold upon itself to form creases due to compressive stresses developed in the dough. Surprisingly, this phenomenon may be related to failures of electrical polymers that are widely used in energy-related applications. Subjected to a voltage, a substrate-bonded polymer film develops a biaxial compressive stress parallel to the film. When the voltage reaches a critical value, the compressive stress induces a pattern of creases on the polymer. If the voltage further rises, the creases strikingly evolve into craters in the polymer, as the electrical stress pulls the creases open. Polymers usually breakdown electrically immediately after the creasing instability, which can cause failures of insulating cables and organic capacitors. The Duke team innovatively introduces a protective layer right beneath the polymer film. The protective layer prevents the electrical breakdown, but allows the team to observe the creasing to cratering instability. If you have any questions, please contact qiming.wang@duke.edu.
Subscribe to:
Post Comments (Atom)
0 comments:
Post a Comment