A steel sheet with a metallic coating is provided. A composition of the metallic coating includes from 2.0 to 24.0% by weight of zinc, from 7.1 to 12.0% by weight of silicon, optionally from 1.1 to 8.0% by weight of magnesium, and optionally additional elements chosen from Pb, Ni, Zr, or Hf. The content by weight of each additional element is less than 0.3%. A balance of the composition is aluminum, unavoidable impurities and residual elements. A ratio Al/Zn is from 4.0 to 6.0.

A lead-free solder preform includes a core layer and adhesion layer coated over surfaces of the core layer, where the preform delivers the combined merits from constituent solder alloys of the core and adhesion layers to provide both high temperature performance and improved wetting in high-temperature solder applications such as die attach. The core layer may be formed of a Bi Alloy having a solidus temperature above 260 C., and the adhesion layer may be formed of Sn, a Sn alloy, a Bi alloy, In, or an In alloy having a solidus temperature below 245 C. The solder preform may be formed using techniques such as: (1) electroplating a core ribbon with an adhesion material, (2) cladding an adhesion material foil onto a core ribbon, and/or (3) dipping a core ribbon in a molten adhesion alloy bath to allow thin layers of adhesion material to adhere to a core ribbon.

A method for producing a hot-dip galvanized steel sheet includes supplying humidified gas to the soaking zone 12 in a manner such that: in passes in which the steel sheet moves upward, the humidified gas is supplied from first humidified gas supply ports 40A to 40E provided at positions higher by 1.0 m or more and 5.0 m or less than the centers of lower hearth rolls 54 and overlapping the steel sheet in the passes when viewed from the side of the soaking zone; and in passes in which the steel sheet moves downward, the humidified gas is supplied from second humidified gas supply ports 42A to 42E provided at positions lower by 1.0 m or more and 5.0 m or less than the centers of the upper hearth rolls 52 and overlapping the steel sheet in the passes when viewed from the side of the soaking zone.

A metallic component includes a core formed of steel. A zinc alloy layer is disposed on the core. The zinc alloy layer is formed of zinc and a very small amount of aluminum, such as 0.14 weight percent or less. A method of creating a component includes providing a steel core, providing a zinc bath consisting of essentially of 0.01 to 0.14 weight percent aluminum, and hot dipping the steel core into the zinc bath to form a zinc coating on the steel core resulting in a zinc-coated steel component. The aluminum may be provided in even lower contents, such as less than 0.08 weight percent, or even less than 0.05 weight percent. The zinc-coated steel component may then be spot welded to another component without first annealing the zinc-coated component. Rather, heat treating is performed locally at the weld joint by the welding procedure alone.

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 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 metallic substrate including at least a first coating consisting of aluminum is provided. The first coating has a thickness between 1.0 and 4.5 m and is directly topped by a second coating based on zinc, such second coating having a thickness between 1.5 and 9.0 m. The thickness ratio of the first coating with respect to the second coating is between 0.2 and 1.2.

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

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

A hot-dip galvanized steel sheet includes: a predetermined chemical composition; and a steel structure represented by: in terms of area ratio, polygonal ferrite: 10% or less; upper bainite: 20% or less; retained austenite: 5% or less; and martensite: 70% or more, in which: martensite having Fe carbides at a number density of 110.sup.6/mm.sup.2 or more is contained by 50% or more, in terms of area ratio, with respect to the entire amount of martensite; and the steel structure has an average effective crystal grain diameter of 5.0 m or less.