Abstract: A spot welding method includes a heating step of energizing an electrode in pressure contact with an Al alloy member to heat and melt a join part by resistance heating and a cooling step of cooling the join part after the heating step in a state in which the electrode is in pressure contact with the Al alloy member. The alloy is a wrought alloy of Mg: 0.2 to 1.2 mass %, Si: 0.4 to 1.5%, and Cu: 1.1% or less or a casting alloy of Si: 7 to 11% and Mg: 0.1 to 0.4% with respect to 100% as a whole. The cooling step includes a first cooling process performed with a reduced amount of input energy to the join part as compared with the heating step and a second cooling process performed after the first cooling process at a higher cooling rate than that in the first cooling process.

Abstract: An example component of a machine includes a core layer and an outer layer encasing the core layer. The outer layer has a greater carbon concentration and hardness than the core layer. The outer layer may also be compressively stressed, while the core layer may have tensile stress. The stress and/or hardness profile of the component may enhance its resistance to cracking, particularly in applications where the component is impacted by other object and/or operates at elevated temperatures. The component, such as parts of a fuel injector, may be formed by rough forming the component, carburizing the component, quenching the component, subzero processing the component, and then performing a tempering process. The components may have relatively sharp transition from the high carbon outer layer to the lower carbon core layer. Additionally, the components have a relatively high tempering resistance when used in relatively high temperature environments.

Abstract: A prosthetic orthopaedic component includes a porous three dimensional structure. The porous three dimensional structure includes post-manufacture residual particles that are to be removed. Methods are therefore disclosed for removing the residual particles and analyzing the particles.

Abstract: The present disclosure relates to an ultra-high-strength plated steel sheet and a method for molding the same, and more particularly, to an ultra-high-strength plated steel sheet having high tensile strength without the occurrence of plating peeling and hydrogen delayed fracture phenomenon during roll forming molding, and a method for molding the same.

Abstract: Examples of methods of hot forming structural components are provided. The methods include heating a blank made from an Ultra High Strength Steel with an aluminum coating and forming the heated blank in a multi-step apparatus.

Abstract: A method and arrangement for the texturing of a moving steel strip wherein a texture is applied to a surface of a moving steel strip by ablation by means of a single laser beam or a plurality of laser beams directed at the surface of the moving steel strip and wherein a liquid is supplied on the moving steel strip over a surface area on the moving steel strip that covers the working area of the single laser beam or the plurality of laser beams on the moving steel strip.

Abstract: A welded steel part with a very high mechanical strength is provided. The welded steel part is obtained by heating followed by hot forming, then cooling of at least one welded blank obtained by butt welding of at least one first and one second sheet. The at least one first and second sheets including, at least in part, a steel substrate and a pre-coating which includes an intermetallic alloy layer in contact with the steel substrate, topped by a metal alloy layer of aluminum or aluminum-based alloy. A method for the fabrication of a welded steel part and the fabrication of structural or safety parts for automotive vehicles are also provided.

Abstract: A 980 MPa-grade hot-rolled ferrite bainite dual-phase steel and a manufacturing method therefor. The chemical components of the steel comprise, in percentage by weight, 0.15-0.30% of C, 0.8-2.0% of Si, 1.0-2.0% of Mn, 0-0.02% of P, 0-0.005% of S, 0-0.003% of O, 0.5-1.0% of Al, 0-0.006% of N, 0.01-0.06% of Nb, 0.01-0.05% of Ti, and the balance of Fe and inevitable impurities. In addition, the chemical components meet the following relations: 0.05%?Nb+Ti?0.10%, and 2.5?Al/C?5.0. The microstructure of the steel is made of ferrite and bainite. The average grain size of the ferrite is 5-10 ?m, and the equivalent grain size of the bainite is less than or equal to 20 ?m. The yield strength of the steel is greater than or equal to 600 MPa, the tensile strength of the steel is greater than or equal to 980 Mpa, and the ductility is greater than or equal to 15%.

Abstract: A welded blank assembly is formed by welding first and second sheet metal pieces together at a weld joint. At least one of the sheet metal pieces includes a boron steel or press hardenable steel base material layer and an aluminum-based coating material layer, along with a weld notch where at least a portion of the coating material layer is removed before welding. An additional material can be provided during welding to influence weld joint composition and/or a secondary heat source can be used to heat and flow a protective material in a weld region of the blank assembly. The weld notch has a width that may be related to the width of a heat-affected zone formed during welding.

Abstract: A welded steel part with a very high mechanical strength is provided. The welded steel part is obtained by heating followed by hot forming, then cooling of at least one welded blank obtained by butt welding of at least one first and one second sheet. The at least one first and second sheets including, at least in part, a steel substrate and a pre-coating which includes an intermetallic alloy layer in contact with the steel substrate, topped by a metal alloy layer of aluminum or aluminum-based alloy. A method for the fabrication of a welded steel part and the fabrication of structural or safety parts for automotive vehicles are also provided.

Abstract: Example systems may include an energy source, a material delivery device, and a computing device. The computing device, based on a target height of a layer deposited on a component by directed energy deposition, may control an energy source directed at a component and may control a material delivery device. Controlling the energy source may include advancing an energy beam along a first path to form an advancing molten pool on the component. Controlling the material delivery device may include delivering a material to the advancing molten pool. The material may combine with the advancing molten pool to form a first raised track having an actual height. The layer may include the first raised track. A deposited region of the component may include the layer. The actual height may affect a resultant microstructure within the deposited region.

Abstract: The invention relates to a method for producing a low-pressure turbine blade from a TiAl material by means of a selective laser melting process, wherein during production in the selective laser melting process the already partially manufactured low-pressure turbine blade is preheated by inductive heating, and wherein the selective laser melting process is carried out under protective gas, the protective gas atmosphere containing contaminants of oxygen, nitrogen, and water vapor in each case of less than or equal to 10 ppm.

Abstract: A method of welding an overlapped portion according to the present invention in which a plurality of steel sheet members are joined at an overlapped portion, and at least one of the plurality of steel sheet members contains martensite, includes: forming a spot-welded portion having a nugget in the overlapped portion; and emitting a laser beam to form a melted and solidified portion crossing an end of the nugget and located between the nugget and a position externally spaced apart from an end of the nugget by not less than 3 mm, this melted and solidified portion being formed in the steel sheet member containing the martensite so as to have a depth of not less than 50% of the thickness of the steel sheet member containing the martensite at a position externally spaced apart from the end of the nugget by 1 mm.

Abstract: A component including a first flange located in a first section of the component, the first flange including a contact surface. The component also including a second flange located in a second section of the component. The first flange is configured to attach to the second flange, and the second flange includes a contact surface configured to contact the contact surface of the first flange. The contact surface of the first flange and the contact surface of the second flange each has an undulating surface profile, where each undulating surface profile is defined by at least one peak point and at least one trough point connected by a curved line extending in at least one of a radial or a circumferential direction relative to a central axis of the component.

Abstract: A steel foil for a power storage device container includes a rolled steel foil which has a thickness of 200 ?m or less, a diffusion alloy layer which is formed on a surface layer of the rolled steel foil and contains Ni and Fe, and a chromium-based surface treatment layer which is formed on the diffusion alloy layer. The <111> polar density in a reverse pole figure of the diffusion alloy layer in a rolling direction is 2.0 to 6.0, and the aspect ratio of crystal in a surface of the diffusion alloy layer is 1.0 to 5.0.

Abstract: A component for a turbomachine having at least one region made of an intermetallic material which is formed from an intermetallic compound or comprises an intermetallic phase as the largest constituent. The intermetallic material is compacted and/or modified in microstructure by microplasticization at least partially at a surface or interface in a region close to the surface or interface.

Abstract: A method of forming a wear resistant and galling resistant coating for abrasive environments and a feed material for the method are disclosed. The feed material is for forming a wear resistant and galling resistant coating on a substrate by a welding process that heats the feed and the substrate. The feed material comprises 35 to 50 wt % titanium nitride particles and a balance of commercially pure titanium or titanium alloy particles and incidental impurities. The method involves delivering the feed material to a surface of a substrate and exposing the feed material and the substrate to sufficient energy to cause at least the commercially pure titanium or titanium alloy particles in the feed to melt and at least some of the titanium nitride particles in the feed to melt, thereby forming a melt pool. On solidification of the melt pool, at least some of the titanium nitride particles are embedded in a matrix formed from melt pool, thereby forming a wear resistant and galling resistant coating on the substrate.

Abstract: The invention relates to a method of forming an AlMg alloy armor plate product, and comprising the steps of: (i) providing a plate product having a gauge of at least 10 mm and a chemical composition, in wt. %: Mg 2.5% to 6%, Mn 0 to 1.2%, Sc 0 to 1%, Ag 0 to 0.5%, Zn 0 to 2%, Cu 0 to 2%, Li 0 to 3%, optionally at least one or more elements selected from the group consisting of (Zr 0.03% to 0.4%, Cr 0.03% to 0.4%, and Ti 0.005% to 0.3%), Fe 0 to 0.4%, Si 0 to 0.25%, inevitable impurities and balance aluminum, and (ii) shaping said alloy plate at a temperature in a range of 200° C. to 400° C. to obtain a predetermined two- or three-dimensional formed structure.

Abstract: A method of determining a quality of a cladding layer according to one aspect of the present invention is a method of determining a quality of a cladding layer 16 formed by irradiating a laser beam 30 while a metallic powder 26 is being supplied, the method including: a process of capturing an image of a melt pool 31 and an area around thereof while the cladding layer 16 is being formed; a process of measuring the sizes and the number of ball-shaped metallic powder aggregates absorbed in the melt pool 31 from the image that has been captured; and a process of determining the quality of the cladding layer 16 based on the sizes and the number that have been measured.

Abstract: The invention relates to a welding device (1), in particular a laser welding device, for welding metal workpieces (3) by means of at least one welding head (2), in particular a laser welding head, which defines a working area (4). The welding device is characterized by at least one heating device (5) which acts on the working area (4) to heat up the workpiece (3), in particular before and/or after the welding process.

Abstract: Direct metal deposition (DMD) is used to fabricate knife edges with extended service life. A metal alloy powder is deposited along a blank and melted with a laser beam so that the powder solidifies into a strip of material having a hardness and/or wear resistance greater than that of the starting material. The piece is then finished to produce a sharp edge in the solidified material. The powder may be melted while it is being deposited, or it may be melted after being deposited. A slot or groove may be formed in the blank with the metal alloy powder being deposited into the slot or groove. A hardened steel alloy powder is deposited onto a mild steel blank. For example, a tool steel or vanadium steel powder may be deposited onto a 1018 steel blank. An invention line-beam nozzle may be used for deposition and/or powder melting.

Abstract: Systems and methods are provided for annealing a semiconductor structure. In one embodiment, the method includes providing an energy-converting structure proximate a semiconductor structure, the energy-converting structure comprising a material having a loss tangent larger than that of the semiconductor structure; providing a heat reflecting structure between the semiconductor structure and the energy-converting structure; and providing microwave radiation to the energy-converting structure and the semiconductor structure. The semiconductor structure may include at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide. The heat reflecting structure may include a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation.

Abstract: Systems and methods for ablating or processing a surface using a laser beam are provided. A method includes directing a laser beam at a surface to form a contact area. The method also includes moving the contact area to form a contact curve. The method includes tuning a wavelength and a power of the laser beam to process a material and/or ablate a coating. The wavelength and the power may be further tuned to not damage the surface beneath the coating. Moving the contact area may include forming a second contact curve by superimposing, at a same time, the second contact curve on the contact curve. A system includes a laser and a directing arrangement configured to direct a laser beam from the laser at a surface to form a contact area. A non-transitory processor-readable medium having instructions stored thereon is provided.

Abstract: A method and apparatus are provided for springing a homogeneous water confinement layer on the surface of a work piece during a laser shock peening process. The method and apparatus are particularly for suitable for forming a homogeneous water layer on a low curvature surface such as found on turbine blades.

Abstract: Methods, systems, and apparatuses are disclosed for temporal pulse shaping of laser pulses used in laser shock peening applications. In one embodiment, a system for temporal pulse shaping of a laser beam used for laser shock peening comprises a laser; a modulator; a high voltage driver, a waveform generator, a polarizer, and an optical amplifier.

Abstract: Systems and methods are provided for annealing a semiconductor structure. In one embodiment, the method includes providing an energy-converting structure proximate a semiconductor structure, the energy-converting structure comprising a material having a loss tangent larger than that of the semiconductor structure; providing a heat reflecting structure between the semiconductor structure and the energy-converting structure; and providing microwave radiation to the energy-converting structure and the semiconductor structure. The semiconductor structure may include at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide. The heat reflecting structure may include a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation.

Abstract: A method for laser heat treatment of high tensile steel is provided to improve for improving formability. The method includes performing a heat treatment by irradiating a surface of a high tensile steel blank that includes a martensite structure and a ferrite structure with a laser to decrease a fraction of the martensite structure and increase a fraction of the ferrite structure. In addition, the method includes slowly cooling the blank to temper or anneal the heat-treated blank and subjecting the cooled blank to cold press forming.

Abstract: Laser assisted bonding for semiconductor die interconnections is disclosed and may, for example, include forming flux on a circuit pattern on a circuit board, placing a semiconductor die on the circuit board where a bump on the semiconductor die contacts the flux, and reflowing the bump by directing a laser beam toward the semiconductor die. The laser beam may volatize the flux and make an electrical connection between the bump and the circuit pattern. A jig plate may be placed on the semiconductor die when the laser beam is directed toward the semiconductor die. Warpage may be reduced during heating or cooling of the semiconductor die by applying pressure to the jig plate. Jig bars may extend outward from the jig plate and may be in contact with the circuit board during the application of pressure to the jig plate. The jig plate may comprise one or more of: silicon, silicon carbide, and glass.

Abstract: A cover glass including a center region and an outer region abutting the center region at an interface. The interface inhibits crack propagation from the outer region to the center region and vice versa. In another embodiment the cover glass may include mitigation voids introduced into the cover glass to inhibit crack propagation. The interface may be formed from the mitigation voids.

Abstract: A process for producing a substrate coated on a face with a low-E thin film multilayer, the process including: depositing a thin-film multilayer containing a thin silver film between at least two thin dielectric films and an absorbent film on a face a substrate; and heat treating the coated face with laser radiation between 500 and 2000 nm to reduce at least one selected from the group of the emissivity and the sheet resistance of the multilayer by at least 5%, wherein the absorbent film at least partially absorbs the laser radiation so that the absorption of the multilayer the wavelength of the laser radiation is such that the absorption of a clear glass substrate 4 mm in thickness coated with the multilayer at the wavelength of the laser radiation is greater than or equal to 10%.

Abstract: Systems and methods are provided for annealing a semiconductor structure. In one embodiment, the method includes providing an energy-converting structure proximate a semiconductor structure, the energy-converting structure comprising a material having a loss tangent larger than that of the semiconductor structure; providing a heat reflecting structure between the semiconductor structure and the energy-converting structure; and providing microwave radiation to the energy-converting structure and the semiconductor structure. The semiconductor structure may include at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide. The heat reflecting structure may include a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation.

Abstract: A hybrid ablation layer that comprises a separate under layer is applied to a material to prevent pitting resulting from laser peening. The underlayer adheres to the surface of the workpiece to be peened and does not have bubbles and voids that exceed an acceptable size. One or more overlayers are placed over and in contact with the underlayer. Any bubbles formed under the over layers are insulated from the surface to be peened. The process significantly reduces the incidence of pits on peened surfaces.

Abstract: The invention concerns a method for making a unitary spark ignition valve, characterized in that it consists in preparing and casting a steel made up in wt. % of: 0.45%?C 0.55%; 12%?Cr?18%; 1%?Si?2.5%; traces?Mn?2%; 0.2%?V?0.5%; traces?Mo?0.5%; 0.05%?N?0.15%, with 0.55%?C+N?0.70%; traces?Ni?1%; traces?Cu?0.25%, or Cu?0.5 Ni if Cu>0.25%; traces?Co?1%; traces?W?0.2%; traces?Nb?0.15%; traces?AI?0.025%; traces?Ti?0.010%; traces?S?0.030%; traces?P?0.040%; traces?B?0.0050%; the balance being iron and impurities resulting from the preparation; in transforming by hot thermomechanical process, for example, by rolling and/or forging between 1000 and 1200° C.; optionally soft annealing, between 650 and 900° C.

Abstract: An objective of the present invention is to provide a rare earth metal-based sintered magnet having imparted thereto sufficient corrosion resistance by an oxidative heat treatment, which is resistant even in an environment of fluctuating humidity, while suppressing the deterioration of the magnetic characteristics ascribed to the oxidative heat treatment, and to provide a method for producing the same.

Abstract: The present invention provides a method for preventing the forming of cracks and slowing the crack propagation in metallic airplane structural parts by laser shock peening with the following steps: Providing an airplane structural part having a crack; irradiating a first surface area of the airplane structural part close to the crack with a first pulsed laser beam having a first wavelength and a first pulsation frequency, wherein energy of the first laser beam is absorbed by the airplane structural part and a shock wave runs through the airplane structural part, which creates compressive prestressings in the airplane structural part.

Abstract: A welding method for welding workpieces made of highly heat-resistant superalloys is provided. The method includes generating a heat input zone on the workpiece surface by means of a heat source, feeding welding filler material into the heat input zone by means of a feeding device, and generating a relative motion between the heat source and the feeding device on one hand and the workpiece surface on the other hand by means of a conveying device. Furthermore, according to the welding method, the mass feed rate is ?350 mg/min.

Abstract: Method for the production of braking elements for vehicles, in particular brake pads, including a die forming step by means of fine and/or traditional shearing of a metal support and a molding step upon the metal support of a block of friction material; the friction material is selected from the group of asbestos free materials, while the metal plate is made of an aluminum alloy selected from the group consisting of aluminum alloys subjected to precipitation hardening (age-hardening alloys) and is made from the fine and/or traditional shearing of a metal sheet when the alloy is in a solubilized state; the alloy, being aged during a friction material baking step, gains its mechanical properties needed for its operation.

Abstract: The present invention disclosed a method of producing a three-dimensional porous tissue in-growth structure. The method includes the steps of depositing a first layer of metal powder and scanning the first layer of metal powder with a laser beam to form a portion of a plurality of predetermined unit cells. Depositing at least one additional layer of metal powder onto a previous layer and repeating the step of scanning a laser beam for at least one of the additional layers in order to continuing forming the predetermined unit cells. The method further includes continuing the depositing and scanning steps to form a medical implant.

Abstract: The present invention provides a laser processing method comprising the steps of attaching a protective tape 25 to a front face 3 of a wafer 1a, irradiating a substrate 15 with laser light L while employing a rear face of the wafer 1a as a laser light entrance surface and locating a light-converging point P within the substrate 15 so as to form a molten processed region 13 due to multiphoton absorption, causing the molten processed region 13 to form a cutting start region 8 inside by a predetermined distance from the laser light entrance surface along a line 5 along which the object is intended to be cut in the wafer 1a, attaching an expandable tape 23 to the rear face 21 of the wafer 1a, and expanding the expandable tape 23 so as to separate a plurality of chip parts 24 produced upon cutting the wafer 1a from the cutting start region 8 acting as a start point from each other.

Abstract: Ni base superalloys containing relatively large amounts of Al and/or Ti are known to be difficult to weld satisfactorily. As the Al and Ti content of the superalloy is increased to improve the strength, the weldability of the component is drastically reduced. It is concluded herein that reducing the ?? phase improves weldability. A stepwise, controlled heating and cooling process is described to be used in cooperation with a welding process to reduce the ?? present and thereby improve weldability.

Abstract: The invention relates principally to a welded steel part with a very high mechanical strength characteristics obtained by heating followed by hot forming, then cooling of at least one welded blank obtained by butt welding of at least one first and one second sheet consisting at least in part of a steel substrate and a pre-coating which is constituted by an intermetallic alloy layer in contact with the steel substrate, topped by a metal alloy layer of aluminum or aluminum-based alloy.

Abstract: A method for producing a product includes the steps of taking heated and cooled extrusion, preferably aluminum, and reheating a selected area of the extrusion. There is the step of requenching the extrusion. There is the step of forming the reheated area into a desired shape. A method for producing a ladder.

Abstract: The invention relates to sheet steel for use as packaging steel, made of a non-alloy or low-alloy and cold-rolled steel having a carbon content of less than 0.1%. According to the invention, in order to use such sheet steel for packaging steel that has good formability and can be produced in a cost-effective way, the sheet steel contains less than 0.4 wt % of manganese, less than 0.04 wt % of silicium, less than 0.1 wt % of aluminum, and less than 0.1 wt % of chromium and is provided with a multi-phase structure, comprising ferrite and at least one of the structure constituents martensite, bainite, and/or residual austenite. The invention further relates to a method for producing such packaging steel from cold-rolled sheet steel.

Abstract: The invention relates to a method for producing packaging steel consisting of a cold-rolled steel sheet made of unalloyed or low-alloy steel having a carbon content of less than 0.1%. In order to provide high-strength packaging steel that has good formability and high corrosion resistance and can be produced in as energy-saving a manner as possible, the steel sheet according to the invention is first coated with a metallic coating and then annealed in a recrystallising manner at a heating rate of more than 75 K/s and preferably more than 100 K/s to temperatures of more than 700° C., such that the metallic coating melts. The coated and annealed steel sheet is then quenched to normal temperature at a cooling rate of at least 100 K/s.

Abstract: A metal implant, in particular a dental implant, with a hydrophilic surface for at least partial insertion into a bone, and a method for the production of said implant are described. A particularly advantageous hydrophilic surface for improved osteointegration properties is made available if it is briefly treated, at least in some areas, in a weakly alkaline solution. These excellent osteointegration properties can be achieved in a method in which, optionally after a preceding mechanical surface modification by material removal and/or chemical surface modification, at least the areas exposed of this surface exposed to bone and/or soft tissue are chemically modified in an alkaline solution.

Abstract: The invention relates to a method of post-weld heat treatment of a without a filler material electron beam or laser welded high strength component made of a gamma prime (??) strengthened superalloy based on Ni or Co or Fe or combinations thereof. The method consists of the following steps a) providing the welded component, then b) heating the welded component by applying a rapid heating-up rate in the range of about 20 to 40° C./min during the entire temperature range from RT up to a temperature T1 of at least 1000° C., then c) holding the welded component at T1 and then heating the component by applying a slow heating-up rate of about 5° C./min to a final temperature Tf, then d) holding the welded component at Tf for a time tf, wherein isothermal dwell time tf is sufficient for at least partially dissolving the gamma prime phase in the weld and also in the base material surrounding the weld; then e) cooling the component with a cooling rate of about 20° C.

Abstract: In order to sharpen and harden a corner portion of a score line edge portion of an iron golf club having a plurality of score lines on a face surface within a prescribed range, heat input is implemented on an edge portion of a groove through laser irradiation after the groove is machined and, as a result, the edge portion is hardened and melted to form a rounded corner R. The hardness is set at a Vickers hardness value (HV) of at least 350. The corner R forms a part of a contour line of the edge portion and this contour line is formed to exist between a first circle that contacts the face surface and a side surface of the groove and has a radius of 0.010 inches (0.254 millimeters) and a second circle that is concentric with the first circle and has a radius of 0.011 inches (0.2794 millimeters).

Abstract: Methods to enhance the quality of grain boundary networks are described. The process can result in the production of a metal including a relatively large fraction of special grain boundaries (e.g., a fraction of special grain boundaries of at least about 55%).

Abstract: In a method for beam welding on components with a laser beam or electron beam generated by a beam source, the heat treatment of the welded component required to remove stresses is integrated into the welding process. In a work cycle combined with the welding process, a regulated heat supply to a selected region takes place, according to its residual heat resulting from the welding process and the predicted stresses in that region, using the residual heat remaining from the welding process following the welding process from the same or other beam source(s). The welding region is cooled in a controlled manner, so that welded components which are likely to be subject to high stress in use, provided for example for a aircraft engine, can be made available without inherent stresses and with the desired microstructure in a single—combined—work step.

Abstract: Disclosed are a preparation method of a steel product capable of local reinforcement using laser heat treatment, and a heat hardened steel used in the method. According to the present invention, the preparation method of a steel part comprises the following steps: (a) preparing a material comprising 0.1-0.5 wt % of C, 0.1-0.5 wt % of Si, 0.5-3.0 wt % of Mn, 0.1 wt % or less of P, 0.05 wt % or less of S, 0.01-1.0 wt % of Cr, 0.1 wt % or less of Al, 0.2 wt % or less of Ti, 0.0005-0.08 wt % of B, and the balance of Fe and inevitable impurities; (b) preparing a formed product by forming the material into a predetermined shape; and (c) locally reinforcing the high strength portion by carrying out laser heat treatment on a portion requiring high strength at the formed product.