The present invention provides a simple, single step and time efficient method and apparatus for developing ultrafine grained microstructure stainless steel having enhanced wear resistance, corrosion resistance, biocompatibility, cellular response and hem-compatibility for bio-implant applications. The processed stainless steel showed 50% reduction in corrosion, high resistance against localised pitting and 50% reduction in wear in simulated body fluid. In addition, the processed steel demonstrated better cell viability, significantly lower platelet adhesion and plasma adsorption signifying high thrombo-resistance and thereby making it highly desirable for bio-implant applications. The present invention eliminates the long processing steps and do not need any specialized equipments and also eliminates the post process treatments.

A metallic material manufactured by a method including steps of (1) subjecting a semifinished metallic billet having at least one of a nanocrystalline microstructure and an ultrafine-grained microstructure 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, wherein the high rate forming process includes a high rate forming process average equivalent strain rate, the high rate forming process average equivalent strain rate being at least about 0.1 s1.

A metallic material manufactured by a method including steps of (1) subjecting a semifinished metallic billet having at least one of a nanocrystalline microstructure and an ultrafine-grained microstructure 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, wherein the high rate forming process includes a high rate forming process average equivalent strain rate, the high rate forming process average equivalent strain rate being at least about 0.1 s1.

Provided is a grain-oriented electrical steel sheet including a steel sheet having a steel sheet surface in which a groove, which extends in a direction intersecting a rolling direction and of which a groove depth direction matches a sheet thickness direction, is formed. When an average value of a groove depth in a sheet thickness direction at a central portion of the groove in a longitudinal groove direction is set as an average groove depth D, a straight line, which connects a first point at which a groove depth in the sheet thickness direction becomes 0.05D and a second point at which the groove depth becomes 0.50D, at an inclined portion of the groove is set as a groove end straight line, an angle made by the steel sheet surface and the groove end straight line is set as a first angle , and an average value of a groove-width-direction length, which is a length of a line segment connecting two points at which a groove depth in the sheet thickness direction in a contour of the groove on the groove-width-direction cross-section becomes 0.05D, is set as an average groove width W, an aspect ratio A obtained by dividing the average groove depth D by the average groove width W, and the first angle satisfy the following Expression (1).
<21A+77(1)

Provided is a grain-oriented electrical steel sheet including a steel sheet having a steel sheet surface in which a groove, which extends in a direction intersecting a rolling direction and of which a groove depth direction matches a sheet thickness direction, is formed. When an average value of a groove depth in a sheet thickness direction at a central portion of the groove in a longitudinal groove direction is set as an average groove depth D, a straight line, which connects a first point at which a groove depth in the sheet thickness direction becomes 0.05D and a second point at which the groove depth becomes 0.50D, at an inclined portion of the groove is set as a groove end straight line, an angle made by the steel sheet surface and the groove end straight line is set as a first angle , and an average value of a groove-width-direction length, which is a length of a line segment connecting two points at which a groove depth in the sheet thickness direction in a contour of the groove on the groove-width-direction cross-section becomes 0.05D, is set as an average groove width W, an aspect ratio A obtained by dividing the average groove depth D by the average groove width W, and the first angle satisfy the following Expression (1).
<21A+77(1)

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.

Methods of strengthening surface regions of high-strength transformation induced plasticity (TRIP) steel are provided. The method may comprise shot peening at least one region of an exposed surface of a hot-formed press-hardened component comprising a high-strength steel. Prior to shot peening, the component has a microstructure comprising about 5% by volume retained austenite in a matrix of martensite. The shot peening is conducted at a temperature of about 150 C. and forms at least one hardened surface region comprising about 2% by volume austenite. The TRIP steel may be zinc-coated and having a surface coating comprising zinc and substantially free of liquid metal embrittlement (LME). Zinc-coated hot-formed press-hardened components, including automotive components, formed from such methods are also provided.

Methods of strengthening surface regions of high-strength transformation induced plasticity (TRIP) steel are provided. The method may comprise shot peening at least one region of an exposed surface of a hot-formed press-hardened component comprising a high-strength steel. Prior to shot peening, the component has a microstructure comprising about 5% by volume retained austenite in a matrix of martensite. The shot peening is conducted at a temperature of about 150 C. and forms at least one hardened surface region comprising about 2% by volume austenite. The TRIP steel may be zinc-coated and having a surface coating comprising zinc and substantially free of liquid metal embrittlement (LME). Zinc-coated hot-formed press-hardened components, including automotive components, formed from such methods are also provided.

A chassis component for a motor vehicle is disclosed. The chassis component (1) is manufactured at least partially from a multi-layer steel sheet (10, 20, 30). The multi-layer steel sheet (10, 20, 30) includes at least three steel layers, including two outer steel layers (11, 12; 21, 22; 31, 32) and one inner steel layer (13, 23, 33). At least one outer steel layer (11, 12; 21, 22; 31, 32) of the multi-layer steel sheet (10, 20, 30) has a tensile strength of at least 1200 MPa. A method for producing a chassis component for a motor vehicle, in particular a wheel (1) or a part thereof, is also disclosed.