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.

The steel material according to the present invention contains, in mass %, C: 0.15 to 0.45%, Si: 0.10 to 1.0%, Mn: 0.10 to 0.8%, P: 0.050% or less, S: 0.010% or less, Al: 0.01 to 0.1%, N: 0.010% or less, Cr: 0.1 to 2.5%, Mo: 0.35 to 3.0%, Co: 0.05 to 2.0%, Ti: 0.003 to 0.040%, Nb: 0.003 to 0.050%, Cu: 0.01 to 0.50%, and Ni: 0.01 to 0.50%, and satisfies the following Formulae. A prior-austenite grain diameter of its microstructure is less than 5 m, and a block diameter of its microstructure is less than 2 m. The microstructure contains a total of 90% by volume or more of tempered martensite and tempered bainite.
C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15Co/6+0.70(1)
(3C+Mo+3Co)/(3Mn+Cr)1.0(2).

Substrate provided with a plurality of layers, at least one of which includes metal oxides and is topped directly by a metal coating layer that contains at least 8% by weight nickel and at least 10% by weight chromium, the remainder being iron, additional elements and the impurities resulting from the fabrication process, wherein this metal coating layer is topped directly by an anticorrosion coating layer. A corresponding fabrication method is also provided.

A welded member includes a hot dip Zn-based alloy coated steel sheet as a base material and has excellent corrosion resistance and weld bead shear strength. In the welded member in which a lower sheet and an upper sheet, which are hot dip Zn-based alloy coated steel sheets, are stacked and arc-welded together, a weld bead is formed so that a cross-sectional width W satisfies the following formula 2TW6T, and a blowhole occupancy Br represented by the following formula (2) becomes not more than 50%: Br=(di/L)100, where T represents a thickness of the hot dip Zn-based alloy coated steel sheet, di represents a length of an i-th blowhole observed in X-ray radiography, and L represents a length of the weld bead.

The invention provides a coated steel including a steel, a coated metal layer coated on a surface of the steel, and an interfacial alloy layer formed at the boundary between the steel and the coated metal layer, in which the coated metal layer has a predetermined composition and structure, and in which the thickness of the coated metal layer is 0.1 m or more, and the thickness of the interfacial alloy layer is 500 nm or less.

A steel sheet for a drawn can has a predetermined chemical composition and has a ferrite single-phase structure with a crystal grain size number of 11.0 or more, the sheet thickness is 0.15 to 0.50 mm, in an L direction of the steel sheet after an ageing treatment at 100 C. for one hour, an yield strength YP is 220 to 290 MPa, a tensile strength TS is 330 to 390 MPa, a total elongation EL is 32% or more, an yield point elongation YP-EL is 0%, an average plastic strain ratio r.sub.m is more than 1.35, and an in-plane anisotropy r is 0.30 to +0.15.

The steel material according to this invention contains, in mass %, C: 0.15 to 0.45%, Si: 0.10 to 1.0%, Mn: 0.10 to less than 0.90%, P: 0.05% or less, S: 0.01% or less, Al: 0.01 to 0.1%, N: 0.01% or less, Cr: 0.1 to 2.5%, Mo: 0.35 to 3.0%, and Co: 0.50 to 3.0%, and satisfies expressions (1) and (2), and contains 90% or more of tempered martensite by volume ratio:
C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15Co/6+0.50(1 )
(3C+Mo+3Co)/(3Mn+Cr)1.0(2 )
Effective B=B11(NTi/3.4)/14(3 ) where, in expression (1) is 0.250 when effective B (mass %) defined by expression (3) is 0.0003% or more, and is 0 when the effective B is less than 0.0003.

A steel sheet including an inner layer and a hard layer at one or both surfaces of the inner layer wherein the hard layer and the inner layer have predetermined compositions, each hard layer has a thickness of 20 m or more and of the total sheet thickness or less, the hard layer has an average micro-Vickers hardness of 400 HV or more and less than 700 HV, the hard layer has an N amount of 0.02% or less, the inner layer has an average micro-Vickers hardness of 80 HV or more and less than 400 HV, the inner layer has a carbide volume ratio of less than 2.00%, and the hard layer has a nanohardness standard deviation of 2.00 or less is provided.

There is provided a high-strength hot-dipped steel sheet having excellent coating adhesion and a method for manufacturing the steel sheet. The steel sheet has a chemical composition, and a coating layer is disposed on the steel sheet. The chemical composition includes, by mass %, C: 0.02% or greater and 0.30% or less, Si: 0.01% or greater and 2.0% or less, Mn: 0.2% or greater and 3.0% or less, P: 0.08% or less, S: 0.02% or less, and Al: 0.001% or greater and 0.40% or less, with the balance being Fe and incidental impurities. The coating layer has a coating weight per side of 30 to 90 g/m.sup.2 and contains exfoliated base steel in an amount of 0.3 to 1.5 g/m.sup.2.

There is provided a hot stamped body including a middle part in sheet thickness and a surface layer arranged at both sides or one side of the middle part in sheet thickness, further including an intermediate layer formed between the middle part in sheet thickness and each surface layer so as to adjoin them, wherein the middle part in sheet thickness has a predetermined composition, the middle part in sheet thickness has a hardness of 500 Hv or more and 800 Hv or less, the surface layer has a hardness change H.sub.1 in the sheet thickness direction of 10 Hv or more and less than 200 Hv, and the intermediate layer has a hardness change H.sub.2 in the sheet thickness direction of 50 Hv or more and less than 200 Hv.