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 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.

The present invention pertains to a hot press forming member having excellent resistance to hydrogen embrittlement, and a method for manufacturing same. An aspect of the present invention provides a hot press forming member having excellent resistance to hydrogen embrittlement, the hot press forming member comprising a base steel plate and an alloy-plated layer formed on the surface of the base steel plate, wherein the alloy-plated layer contains pores such that pores having a size of 5 ?m or less constitute 3-30% of the surface area of the alloy-plated layer as viewed in a cross-section taken in the thickness direction of the member.

The present invention provides a method for manufacturing a metal sheet. In this method, at least one of the following equations is satisfied: $\begin{array}{cc}\frac{Z}{d}+18\ln \left(\frac{Z}{d}\right)<8\ln \left(\frac{P}{V}\right)-27.52& \left(A\right)\\ {\mathrm{fO}}_2<\frac{2.304.Math.{10}^{-3}}{{(27.52+\frac{Z}{d}+8\ln (\frac{V}{P}}^{}}\end{array}$

A high-strength steel sheet that has a predetermined component composition, that has a steel microstructure in which an area percentage of ferrite ranges from 5% to 50% in a thickness cross-section in a rolling direction, a total area percentage of fresh martensite and retained ranges from 2% to 30%, each of the fresh martensite and the retained has an average grain size of 5 m or less, and a ratio of the fresh martensite and the retained adjacent only to ferrite with respect to the fresh martensite and the retained from a surface to 200 m in the thickness direction is 30% or less in total area percentage, and that has a yield strength of 550 MPa or more.

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.

The present invention provides a method for manufacturing a metal sheet. In this method, at least one of the following equations is satisfied:

[00001]$\begin{array}{cc}\frac{Z}{d}+18.Math..Math.\ln \left(\frac{Z}{d}\right)<8.Math..Math.\ln \left(\frac{P}{V}\right)-27.52& \left(A\right)\\ f.Math..Math.O_2<\frac{2.304.Math.{\mathrm{.10}}^{-3}}{{\left(27.52+\frac{Z}{d}+8.Math..Math.\ln \left(\frac{V}{P}.Math.{\left(\frac{Z}{d}\right)}^{2.25}\right)\right)}^2}& \left(B\right)\end{array}$

wherein: Z is the distance between the metal sheet and the nozzle along the main ejection direction (E), Z being expressed in mm, d is the average height of the outlet of the nozzle along with the running direction of the metal sheet in front of the nozzle, d being expressed in mm, V is the running speed of the metal sheet in front of the nozzle, V being expressed in m.Math.s.sup.1, P is the pressure of the wiping gas in the nozzle, P being expressed in N.Math.m.sup.2, and fO.sub.2 is the volume fraction of oxygen in the wiping gas. A metal sheet, part and land motor vehicle are also provided.

According to an embodiment of the invention, a rolling equipment includes two coiler furnaces; a plurality of mill stands provided between the two coiler furnaces, the plurality of mill stands being for reverse rolling; and an induction heater provided between the plurality of mill stands, the induction heater implementing a heated temperature increase in a designated reverse rolling or in each reverse rolling, the heated temperature increase being in a hot strip longitudinal direction and width direction. Thus, the hot strip temperature distribution can be improved.

A steel part includes a steel sheet substrate and a coating on at least one surface of the steel sheet substrate. The coating includes between 0.2 and 0.7% by weight of Al, with a remainder of the metal coating being Zn and inevitable impurities. The steel sheet substrate and the coating have at least one deformation. An outer surface of the coating has a waviness Wa.sub.0.8 of less than or equal to 0.43 m.

A coated metal sheet includes a steel substrate and a coating on at least one surface of the steel substrate. The coating includes between 0.2 and 0.7% by weight of Al, with a remainder of the metal coating being Zn and inevitable impurities. The coated metal sheet was subjected to a skin pass operation after coating. An outer surface of the metal coating has a waviness Wa.sub.0.8 of less than or equal to 0.55 m.