Provided is a thin, narrow tube for use in a biodegradable medical device formed from a round tube made of a magnesium material as the base material, in which a desired outer diameter and an inner diameter are provided with good precision over the entire region in a longitudinal direction and a circumferential direction, and the length of biodegradation time can be controlled without changing a material composition. The thin, narrow tube is a thin, narrow tube of a biodegradable medical device, in which the thin, narrow tube is a round tube made of crystals containing magnesium (Mg) having a hexagonal crystal structure, and when the crystals forming the round tube are viewed in a round tube axis direction of the round tube, a hexagonal basal plane (0001) is oriented at a predetermined inclination angle with respect to a circumferential direction perpendicular to a radial direction (a direction from an inner surface to an outer surface) of the round tube.

Provided is a thin, narrow tube for use in a biodegradable medical device formed from a round tube made of a magnesium material as the base material, in which a desired outer diameter and an inner diameter are provided with good precision over the entire region in a longitudinal direction and a circumferential direction, and the length of biodegradation time can be controlled without changing a material composition. The thin, narrow tube is a thin, narrow tube of a biodegradable medical device, in which the thin, narrow tube is a round tube made of crystals containing magnesium (Mg) having a hexagonal crystal structure, and when the crystals forming the round tube are viewed in a round tube axis direction of the round tube, a hexagonal basal plane (0001) is oriented at a predetermined inclination angle with respect to a circumferential direction perpendicular to a radial direction (a direction from an inner surface to an outer surface) of the round tube.

A method for production of a metallic material from a semifinished metallic billet, the semifinished metallic billet including a nanocrystalline microstructure and/or an ultrafine-grained microstructure, the method including the steps of (1) subjecting the semifinished metallic billet to a rotary incremental forming process to form an intermediate wrought metallic billet, and (2) subjecting the intermediate wrought metallic billet to a high rate forming process to form a metallic product.

A method for production of a metallic material from a semifinished metallic billet, the semifinished metallic billet including a nanocrystalline microstructure and/or an ultrafine-grained microstructure, the method including the steps of (1) subjecting the semifinished metallic billet to a rotary incremental forming process to form an intermediate wrought metallic billet, and (2) subjecting the intermediate wrought metallic billet to a high rate forming process to form a metallic product.

Rather than using a conventional stamping forming process with steels having high ultimate tensile strength and relatively low initial yield, tubular hydroforming techniques are introduced to synergize with BIW part forming, or forming of other load bearing parts. Such steels can have ultimate tensile strengths of greater than 1000 MPa and initial yields of less than 360 MPa In some embodiments, the steels have elongation of at least 40%. Such steels can include retained austenite.

Rather than using a conventional stamping forming process with steels having high ultimate tensile strength and relatively low initial yield, tubular hydroforming techniques are introduced to synergize with BIW part forming, or forming of other load bearing parts. Such steels can have ultimate tensile strengths of greater than 1000 MPa and initial yields of less than 360 MPa In some embodiments, the steels have elongation of at least 40%. Such steels can include retained austenite.

A thermally stabilized fastener system and method is disclosed. The disclosed system/method integrates a fastener (FAS) incorporating a faster retention head (FRH), fastener retention body (FRB), and fastener retention tip (FRT) to couple a mechanical member stack (MMS) in a thermally stabilized fashion using a fastener retention receiver (FRR). The MMS includes a temperature compensating member (TCM), a first retention member (FRM), and an optional second retention member (SRM). The TCM is constructed using a tailored thermal expansion coefficient (TTC) that permits the TCM to compensate for the thermal expansion characteristics of the FAS, FRM, and SRM such that the force applied by the FRH and FRR portions of the FAS to the MMS is tailored to a specific temperature force profile (TFP) over changes in MMS/FAS temperature. The TCM may be selected with a TTC to achieve a uniform TFP over changes in MMS/FAS temperature.

A method for manufacturing a metal structure (130) for use in a downhole assembly comprises plastically deforming at least a portion of the metal structure (130); and heating at least the deformed portion of the metal structure to a temperature below its critical and/or transformation temperature. An assembly for performing the method comprises a production fixture (370) configured to receive the metal structure (130), wherein the production fixture is adapted to undergo heating to a temperature below and/or up to the critical and/or transformation temperature of the metal structure. By heating at least the deformed portion of the metal structure to a temperature below its critical and/or transformation temperature, the metal structure may undergo stress relief, which may help prevent undesirable movement of deformed portion, e.g. collet fingers of a catching apparatus, against the direction of deformation after impact(s) and/or shock(s) from moving objects, in use.

A method for manufacturing a metal structure (130) for use in a downhole assembly comprises plastically deforming at least a portion of the metal structure (130); and heating at least the deformed portion of the metal structure to a temperature below its critical and/or transformation temperature. An assembly for performing the method comprises a production fixture (370) configured to receive the metal structure (130), wherein the production fixture is adapted to undergo heating to a temperature below and/or up to the critical and/or transformation temperature of the metal structure. By heating at least the deformed portion of the metal structure to a temperature below its critical and/or transformation temperature, the metal structure may undergo stress relief, which may help prevent undesirable movement of deformed portion, e.g. collet fingers of a catching apparatus, against the direction of deformation after impact(s) and/or shock(s) from moving objects, in use.

The present invention provides a deformed part created by forming a coated metal sheet into a part, the coated metal sheet comprising a steel substrate, at least one face of which is coated with a metal coating deposited by dipping the substrate in a bath, said coating comprising between 0.2 and 0.7% by weight of Al, the remainder of the metal coating being Zn and inevitable impurities, wherein an outer surface of a metal coating of the deformed part has a waviness Wa0.8 of less than or equal to 0.43 ?m.