A downhole motor or pump assembly that includes a stator and a rotor rotatable within the stator. The stator includes a tubular housing and an overlay deposited by cold spray onto an interior of the housing to form overlay lobes along a first length of the stator. The downhole motor or pump may be used to perform downhole operations.

One aspect of the present invention is a lubricant to be incorporated into a powder metallurgical mixed powder containing an iron-based powder. The lubricant includes a flaky organic material having an average particle diameter of from 0.1 μm to less than 3 μm. Another aspect of the present invention is a powder metallurgical mixed powder which contains an iron-based powder and the lubricant. Yet another aspect of the present invention is a method for producing a sintered compact. The method includes the step of mixing materials to give a powder metallurgical mixed powder containing an iron-based powder and the lubricant. The powder metallurgical mixed powder is compacted using a die to give a powder compact. The powder compact is sintered to give a sintered compact.

A lubrication board includes a substrate; and a lubrication layer disposed on a surface of the substrate, wherein the lubrication layer comprises a polymer expressed by formula (I) below,

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wherein R.sub.1 is selected from a substituted or unsubstituted C.sub.6-C.sub.18 alkyl; R.sub.2 is selected from a substituted or unsubstituted C.sub.2-C.sub.18 alkyl or C.sub.2-C.sub.18 alkyl which is interrupted by —O—; R.sub.3 is selected from —NH— or —S—; R.sub.4 is selected from —NH.sub.2, —OH or —SH; and n, p and q are positive integers ranging from 2 to 20000.

A solid lubricant bar comprising hydrogenated castor oil or wax, expandable flake graphite, and copper. ATH, MDH, and zinc borate can also be added to the formulation to enhance fire retardancy and suppression.

A lubricant including a plurality of segments including a divalent center segment and two sidechain segments, each including a perfluoroalkyl ether moieties is provided in which a dewetting thickness of the lubricant may be determined based in-part on a segment weight average molecular weight of the segments. A magnetic recording medium and a magnetic data storage system including the lubricant are also provided.

Some variations provide a low-adhesion coating comprising a continuous matrix containing a first component, a plurality of inclusions containing a second component, and a solid-state lubricant distributed within the coating, wherein one of the first component or the second component is a low-surface-energy polymer, and the other of the first component or the second component is a hygroscopic material. The solid-state lubricant may be selected from graphite, graphene, molybdenum disulfide, tungsten disulfide, hexagonal boron nitride, or poly(tetrafluoroethylene) or other fluoropolymers. The solid-state lubricant particles may be coated with a metal selected from cadmium, lead, tin, zinc, copper, nickel, or alloys containing one or more of these metals. The solid-state lubricant is typically characterized by an average particle size from about 0.1 μm to about 500 μm. The solid-state lubricant is preferably distributed throughout the coating.

A method of producing a compacted article according to one embodiment may involve the steps of: Providing a copper/molybdenum disulfide composite powder including a substantially homogeneous dispersion of copper and molybdenum disulfide sub-particles that are fused together to form individual particles of the copper/molybdenum disulfide composite powder; and compressing the copper/molybdenum disulfide composite powder under sufficient pressure to cause the copper/molybdenum disulfide composite powder to behave as a nearly solid mass.

The fluorine-containing ether compound is represented by the following formula (1): R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4. In the formula (1), R.sup.1 is represented by the following formula (2), R.sup.2 is represented by the following formula (3), R.sup.3 is a perfluoropolyether chain, and R.sup.4 is an organic end group different from R.sup.1—R.sup.2— and contains two or three polar groups, wherein each polar group is bonded to a different carbon atom, and the carbon atoms to which the polar groups are bonded are bonded to one another via a linking group containing a carbon atom to which the polar group is not bonded. In the formula (2), R.sup.5 is an alkoxy group selected from the group consisting of a methoxy, an ethoxy and a propoxy group. In the formula (3), w is 2 or 3.

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The present invention provides a novel surface-modified inorganic substance obtained by modifying the surface of an inorganic nitride or an inorganic oxide with a boronic acid compound, and a heat dissipation material, a thermally conductive material, and a lubricant which use the surface-modified inorganic substance. The present invention also provides a method for manufacturing the surface-modified inorganic substance, and provides, as a novel method for modifying the surface of an inorganic substance selected from an inorganic oxide and an inorganic nitride with an organic substance, a method for modifying the surface of an inorganic nitride or an inorganic oxide with an organic substance that includes making a contact between the inorganic nitride or the inorganic oxide with a boronic acid compound.

A lubrication structure for a shock absorber of vehicle has a protecting pipe and a self-lubricating layer. The protecting pipe is a non-circular metal tube and has an elongated slit. The self-lubricating layer is an engineering plastic layer, is deposited in the protecting pipe and has a shaft hole. When the lubrication structure is deposited between an outer tube and an inner tube of a shock absorber of vehicle, the protecting pipe engages in the outer tube to prevent the self-lubricating layer from contacting the outer tube directly. The self-lubricating layer with small friction coefficient is mounted around the inner shaft to enable the inner shaft to move smoothly relative to the outer tube. The lubrication structure has characteristics of low cost, small volume, and small tolerance, and the life and the practicality of the lubrication structure can be improved.