摘要:
A multilayer construction for an array of aerodynamic riblets incorporates a first layer composed of a material with protuberances, the first layer material having shape memory and a second layer composed of a material exhibiting a second characteristic with capability for adherence to a surface.
摘要:
A prepreg material infused with a bulk resin, where the bulk resin has shape memory alloy (SMA) particles intermixed in the resin to toughen the material when the material is used in an application and is cured. The SMA particles may be of various shapes and sizes. The material may form a prepreg fabric having interwoven fibers or a prepreg unidirectional tape having fibers oriented unidirectionally. Opposing surfaces of the material may be infused with quantities of bulk resin having different concentrations of SMA particles. The SMA particles may be mixed in the bulk resin while in their austenitic or martensitic states to suit the needs of specific applications.
摘要:
Striking implements that have an improved ability to store and quickly release significant energy during flexure and at the same time have significant vibration damping capability to impart a desired “feel” to the user. A shape memory alloy element is inserted at a specific flex point along the length of the sports or utility striking implement to permit a desired degree of flexure, with an enhanced leverage effect, and to absorb undesired vibrational energy. Typical sports or utility striking implements utilizing the invention include, but are not limited to, golf clubs, hockey sticks, polo clubs, tennis rackets, racket ball rackets, baseball bats, pole vaults, rowing oars, picks, axes, hammers, and the like.
摘要:
A composite prepreg material (10) with improved resistance to core crush and porosity incorporates a plurality of different fiber forms having varying cross-sectional configurations. Preferably, the fibers are interwoven in a warp (14) and fill (18) perpendicular orientation pattern. The varying cross-sectional configurations of the different fiber forms causes the fiber forms to have different levels of spreadability and frictional resistance to movement of the fiber. The present invention overcomes the susceptibility to many defects (specifically core crush and porosity) associated with composite material of a single fiber form having a set cross-sectional configuration, by incorporating multiple fiber forms having varying cross-sectional configurations. This multi-fiber form incorporation allows the strengths of one fiber form's properties to help compensate for the weaknesses of another fiber form's properties, and vice versa. Many variations of multi-fiber form woven designs can be utilized that incorporate fiber forms such as ST (standard twist tows); UT (untwisted tows, i.e. previously twisted and then untwisted tows); and NT (never twisted tows).
摘要:
A novel method of forming high strength, fiber reinforced, high temperature thermoplastic panels is provided which entails placing at least one layer of metal mesh or screen adjacent the vacuum probes in a vacuum bagging apparatus. Additionally, caul plates are placed as needed around the thermoplastic workpiece and metal mesh is positioned on the plates to promote uniform vacuum drawing on the entire panel and complete consolidation.
摘要:
A multilayer construction for an array of aerodynamic riblets incorporates a first layer composed of a material with protuberances, the first layer material having shape memory and a second layer composed of a material exhibiting a second characteristic with capability for adherence to a surface.
摘要:
A prepreg material infused with a bulk resin, where the bulk resin has shape memory alloy (SMA) particles intermixed in the resin to toughen the material when the material is used in an application and is cured. The SMA particles may be of various shapes and sizes. The material may form a prepreg fabric having interwoven fibers or a prepreg unidirectional tape having fibers oriented unidirectionally. Opposing surfaces of the material may be infused with quantities of bulk resin having different concentrations of SMA particles. The SMA particles may be mixed in the bulk resin while in their austenitic or martensitic states to suit the needs of specific applications.
摘要:
A polymer composite structure having resin matrix interlayers reinforced with shape memory alloy (SMA) particles. In one preferred form Nitinol® alloy particles are used for the SMA particles. The Nitinol® alloy particles may comprise cylindrical, oval or spherical shaped particles and are intermixed in the resin of the resin matrix interlayer(s) of the composite structure. The SMA particles provide superelastic, reversible strain properties that significantly improve the damage resistance, damage tolerance (e.g. compression-after-impact (CAI) strength) and elevated temperature performance of the composite structure without negatively affecting the hot-wet compression strength of the composite structure. The polymer composite structure is ideally suited for aerospace and aircraft applications where lightweight and structurally strong materials are essential.
摘要:
A composite prepreg material (10) with improved resistance to core crush and porosity incorporates a plurality of different fiber forms having varying cross-sectional configurations. Preferably, the fibers are interwoven in a warp (14) and fill (18) perpendicular orientation pattern. The varying cross-sectional configurations of the different fiber forms causes the fiber forms to have different levels of spreadability and frictional resistance to movement of the fiber. The present invention overcomes the susceptibility to many defects (specifically core crush and porosity) associated with composite material of a single fiber form having a set cross-sectional configuration, by incorporating multiple fiber forms having varying cross-sectional configurations. This multi-fiber form incorporation allows the strengths of one fiber form's properties to help compensate for the weaknesses of another fiber form's properties, and vice versa. Many variations of multi-fiber form woven designs can be utilized that incorporate fiber forms such as ST (standard twist tows); UT (untwisted tows, i.e. previously twisted and then untwisted tows); and NT (never twisted tows).