摘要:
One embodiment of the invention includes an MR fluid of improved durability. The MR fluid is particularly useful in devices that subject the fluid to substantial centrifugal forces, such as large fan clutches. A particular embodiment includes a magnetorheological fluid including a liquid, magnetizable particles, a stearate and a thiophosphate.
摘要:
A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof. The hook portion includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof, wherein the plurality of hook elements comprises a fiber and a shape memory alloy coating deposited onto the fiber, and wherein the fiber and the shape memory alloy coating comprises a non-axisymmetric coating or deposition of the shape memory alloy about a portion of the fiber. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. Introducing a thermal activation signal to the plurality of hook elements causes a change in shape orientation, flexural modulus property, or a combination thereof that is effectively reduces the shear and/or pull off forces in the releasable engagement. In this manner, disengagement of the releasable fastener system provides separation of the hook portion from the loop portion under controlled conditions.
摘要:
One exemplary embodiment includes a method comprising providing a tire having a component constructed and arranged to cause at least one portion of the tire to have a first stiffness or resistance to force exerted thereon under a first condition and a second stiffness or resistance to force exerted thereon under a second condition and selectively causing the first or second condition to occur.
摘要:
A method for forming a part with a tooling assembly includes forming an MRF bladder located within the tooling assembly into a desired shape, then placing the part in the tooling assembly, and forming the part with the tooling assembly by applying pressure until the part obtains the desired shape from the MRF bladder.
摘要:
A microfibrous article includes a substrate and a plurality of magnetic fibers disposed on the substrate. Each of the plurality of magnetic fibers is individually sheathed with a polymer and includes a plurality of magnetic particles. Further, each of the plurality of magnetic fibers is aligned along a magnetic field and not connected by the polymer to any adjacent magnetic fiber. A method of forming the microfibrous article is also disclosed.
摘要:
An apparatus is provided having an active material forming a surface thereof in contact with a rheological fluid. The active material is controllable to vary a surface geometry thereof between a rough or nonsmooth surface geometry to increase drag, and achieve an increase in stress transmitted through the fluid, when a field is applied, while allowing a smooth surface geometry and an associated reduction in stress transmitted through the fluid when the field is removed. A method of enhancing performance of an apparatus that includes a rheological fluid is also provided.
摘要:
A fluid includes a liquid medium having iron particles mixed therein. An organic phosphonate based coating is established on the iron particles. The organic phosphonate based coating does not substantially include phosphonic acid groups at an outer surface thereof, and increases oxidation resistance of the iron particles. A method of making such a liquid medium is also disclosed herein.
摘要:
A magnetorheological fluid composition comprising a low aspect ratio magnetizable particle comprising a unimodal particle distribution and an aspect ratio less than 1.5, a high aspect ratio magnetizable particle comprising an aspect ratio greater than 1.5, and a carrier fluid.
摘要:
A magnetorheological fluid composition comprising a carrier fluid; and a plurality of high aspect ratio magnetizable particles, wherein the aspect ratio of the high aspect ratio magnetizable particles is greater than 1.5. Optionally, the high aspect ratio magnetizable particles can have interlocking structures comprising male component and a female component. Still further, a magnetorheological fluid composition can comprise low aspect ratio magnetizable particles having the interlocking structures, wherein the aspect ratio of the low aspect ratio magnetizable particles is 1 to 1.5.
摘要:
A magnetorheological (MR) fluid coupling for vectoring torque with respect to a shaft capable of rotary motion is disclosed. The coupling includes a stator, a rotor having a rotational degree of freedom with respect to the stator and configured for physical communication with the shaft, and a magnetic field generator. The stator and rotor define an annular space therebetween and are coupled via a MR fluid disposed within the annular space. The magnetic field generator is in field communication with the MR fluid and is disposed to produce a substantially radially directed magnetic field across the annular space. The rotor is rotationally responsive to the application of a magnetic field at the MR fluid.