This invention provides a joint product between a steel product and an aluminum material, which can realize spot welding with high bonding strength, and a spot welding method for the joint product. In one embodiment, a steel product (1) having a sheet thickness t1 of 0.3 to 3.0 mm is joined to an aluminum material (2) having a sheet thickness t2 of 0.5 to 4.0 mm by spot welding to form a joint product between the steel product and the aluminum material. The joint product is characterized in that the nugget area in the joint is 20 × t20.5 to 100 × t20.5 mm2, the area of a part where the thickness of an interface reaction layer is 0.5 to 3 µm, is not less than 10 × t20.5 mm2, and the difference in thickness of the interface reaction layer between the joint center and a point distant from the joint center by a distance of one-fourth of the joint diameter DC is not more than 5 μm. The above constitution can provide a high-bonding strength joint product, between dissimilar materials, which can be formed without newly using other materials such as clad materials and without newly adding a separate step using an existing spot welding apparatus at low cost, and a spot welding method.

Joint product between steel product and aluminum material, spot welding method for the joint product, and electrode chip for use in the joint product

A fastener assembly includes a row of fasteners having a head, a tip, and a portion of a shank coated with a polymer composition. The polymer composition includes a polymer material such as polyurethane and metal particles. The polymer composition is used to provide improved corrosion and ultraviolet radiation resistance when used with naturally corrosive or pressure preservative treated wood. The fastener assembly is coated with the polymer composition by vacuum coating a dispersion of the polymer composition in a solvent such as water and removing the solvent.

Partially coated fastener assembly and method for coating

A steel strip that has a coating of an Al-Zn-Si alloy that contains 0.3-10 wt.% Mg and 0.005-0.2 wt.% V.

Metal-coated steel strip

An aluminum-plated steel sheet for hot pressing is provided which is free from the conventional problem that an aluminum-plated steel sheet, when applied to hot pressing, suffers aluminum melting during preheating for the hot pressing. The steel sheet is further free from the problem concerning delayed fracture caused by residual hydrogen. Also provided are: a process for producing the aluminum-plated steel sheet; and a method of hot pressing with rapid heating in which the aluminum-plated steel sheet is used. The aluminum-plated steel sheet for hot pressing is produced by annealing an aluminum-plated steel sheet in a coiled state in an annealing box furnace under holding-time and temperature conditions which are within the range shown in Fig 5, whereby the aluminum deposit is alloyed with the steel sheet. The method of hot pressing with rapid heating is characterized in that a blank cut out of the aluminum-plated steel sheet for hot pressing is preheated at a heating rate of 40 DEG C/sec or higher on the average so that the time period over which the blank is exposed to an environment of 700 DEG C or higher is 20 seconds or shorter, and the preheated blank is hot-pressed.

Aluminum-plated steel sheet for hot pressing with rapid heating, process for producing same, and method of hot-pressing same with rapid heating

The invention relates to a method for producing hardened parts from sheet steel, comprising the following method steps: a) shaping formed parts made from a sheet steel provided with a cathodic corrosion protection, whereby; b) before, during or after shaping the formed part, a necessary end trimming of the formed part and, if necessary, required stampings or the production of a hole pattern is carried out, whereby; c) the formed part is subsequently heated, at least in partial areas and with the admission of atmospheric oxygen, to a temperature that enables an austenitizing of the steel material, and; d) the part is then transferred into a shape hardening tool, a shape hardening is carried out inside the shape hardening tool, during which the part is cooled and hardened by setting and pressing the part through the shape hardening tools.

Method for producing hardened parts from sheet steel

PROBLEM TO BE SOLVED: To obtain a hot dip Zn-Al-Mg plated steel sheet good in corrosion resistance and surface appearance. SOLUTION: This hot dip Zn base plated steel sheet is the one in which a hot dip Zn-Al-Mg plating layer contg., by weight, 4.0 to 10% Al, 1.0 to 4.0% Mg, and the balance Zn with inevitable impurities is formed on the surface of a steel sheet, and the plating layer has a metallic structure in which [primary crystal Al plases] or [primary crystal Al phases] and [Zn single phases] are coexistent in the basis of [the ternary eutectic structure of Al/Zn/Zn 2 Mg]. COPYRIGHT: (C)1998,JPO

Hot dip zinc-aluminum-magnesium plated steel sheet good in corrosion resistance and surface appearance and its production

PROBLEM TO BE SOLVED: To obtain hot dip Zn-Al-Mg based alloy plated steel which has high corrosion resistance even with a drenching method where steel formed into a prescribed shape is dipped into a hot dip plating bath. SOLUTION: In the plated steel, a plated layer having a composition containing, by mass, 0.005 to 30.0% Al and 0.5 to 10.0% Mg, and the balance substantially Zn is formed on the surface of base steel via an alloy layer consisting of one or two kinds selected from an Fe2 Al5 intermetallic compound and an FeAl3 intermetallic compound. A structure where the plated layer infiltrates into the gaps of the alloy layer, and one or two kinds selected from an Fe2 Al5 intermetallic compound, an FeAl3 intermetallic compound, an Fe-Zn based intermetallic compound and an Fe-Zn-Al based amorphous compound are dispersed therein is preferable.

HOT DIP Zn-Al-Mg BASED ALLOY PLATED STEEL HAVING EXCELLENT CORROSION RESISTANCE

PROBLEM TO BE SOLVED: To obtain a hot dip Zn-Al-Mg coated steel sheet excellent in external surface appearance as well as in corrosion resistance by using in-line annealing type continuous hot dipping equipment. SOLUTION: This steel sheet is a hot dip Zn-base alloy coated steel sheet prepared by forming a plating layer, having a composition consisting of, by weight, 4.0-10.0% Al, 1.0-4.0% Mg, 0.002-0.1% Ti, 0.001-0.045% B, and the balance Zn with inevitable impurities, on the surface of a steel sheet. Moreover, the plating layer has a metallic structure where [primary-crystal Al phases] or [primary-crystal Al phases] and [Zn single phases] are present as a mixture in a matrix of [ternary eutectic structure of Al/Zn/Zn 2 Mg]. COPYRIGHT: (C)1998,JPO

Hot dip zn-al-mg coated steel sheet excellent in corrosion resistance and external surface appearance, and its production

A steel sheet hot dip coated with Zn-Al-Mg having a high Al content, characterized in that it comprises a steel sheet and, formed on the surface thereof, a hot dip coating layer having a chemical composition: Al: more than 10 % and 22 % or less, Mg: 1 to 5 % and, optionally in addition, Ti: 0.002 to 0.1 %, B: 0.001 to 0.045 %, Si: 0.005 to 0.5 %, and balance: Zn and inevitable impurities, and the hot dip coating layer has a metal structure composed of a base of a ternary eutectic structure of Al/Zn/Zn2Mg and primary crystal phases of Al being included in the base, and preferably, the metal structure of the hot dip coating layer is substantially free of a phase based on Zn11Mg2.

Steel sheet hot dip coated with Zn-Al-Mg having high Al content

PROBLEM TO BE SOLVED: To provide a high tensile galvannealed steel sheet which exhibits a high tensile force of ≥580 Mpa, is improved in molten metal embrittlement resistance during spot welding, and is excellent in weldability and workability. SOLUTION: The composition of the base steel (each by mass%) of the steel sheet comprises 0.04 to 0.25% C, 0.01 to 2.0% Si, 0.5 to 3.0% Mn, ≤0.1% P, ≤0.03% S, further one or two or more kinds of 0.001 to 0.1% Ti, 0.001 to 0.1% Nb, 0.01 to 0.3% V, 0.01 to 0.5% Mo, 0.01 to 0.5% Zr, comprises, as necessary, 0.0001 to 0.01% B, wherein the metal structure comprises one or two or more kinds of a ferrite phase, bainite phase, pearlite phase and martensite phase of 40 to 95% in area rate, and the balance 1 to 10% volume fraction residual austenite phase. The metal structure is preferably dispersed with the deposited material or compound deposited material of Ti, Nb, V, Mo, and Zr of 3 to 200 nm in average grain size. COPYRIGHT: (C)2007,JPO&INPIT

Ando Atsushi

Papers

Hot dip zinc-aluminum-magnesium plated steel sheet good in corrosion resistance and surface appearance and its production

HOT DIP Zn-Al-Mg BASED ALLOY PLATED STEEL HAVING EXCELLENT CORROSION RESISTANCE

Hot dip zn-al-mg coated steel sheet excellent in corrosion resistance and external surface appearance, and its production

Steel sheet hot dip coated with Zn-Al-Mg having high Al content

High tensile galvannealed steel sheet having excellent workability and molten metal embrittlement crack reistance