The present invention relates to a hot-rolled steel sheet for a high strength galvanized steel sheet, having excellent surface quality, and a method for producing the same, the hot-rolled steel sheet comprising, by weight %: C: 0.05 to 0.15%, Si: 0.03 to 0.10%, Mn: 0.7 to 1.39%, P: 0.001 to 0.05%, S: 0.001 to 0.03%, Al: 0.002 to 0.035%, and the remainder being Fe and unavoidable impurities. The weight ratio of Mn/Si is 15 to 25, the weight ratio of C/Si is 1 to 5, and the weight ratio of Si/P is 3 to 10. The hot-rolled steel sheet has a microstructure consisting of, in area fraction, 10 to 40% of bainite, 20 to 30% of pearlite and 40 to 60% of ferrite, and includes a ternary eutectic compound of FeO, Fe.sub.2SiO.sub.4 and Fe.sub.3(PO).sub.4 formed within 50 μm from the surface.

A coating made of platinum-gold alloy is provided, together with a method of its preparation by electrodeposition. The alloy is composed of more than 50 atomic percent platinum. The microstructure of the alloy consists of generally ellipsoidal grains. More than half of the grains have a major axis of 10 nm or less.

A coated tool according to the present disclosure comprises a base body and a coating film. The base body is made of a cemented carbide or a cermet. The coating film is located on the base body. In a case where a hardness is measured by pressing an indenter from a surface of the coating film to a depth of 20% of the coating film while changing an indentation load of the indenter, when a minimum hardness of the hardness is defined as a first hardness, a maximum hardness of the hardness is defined as a second hardness, a depth at the first hardness is defined as a first hardness depth, and a depth at the second hardness is defined as a second hardness depth, the second hardness depth is smaller than the first hardness depth, and a difference therebetween is greater than 7 GPa.

One aspect of the disclosure provides an iron-based hardfacing layer which includes hard or wear resistant phases resulting at least in part from dissolution of silicon and/or boron carbide particles into a liquid iron-based metal during the fabrication process. In an embodiment, the hardfacing layer is formed by a fusion welding process in which carbide particles are added to the molten weld pool. In an example, the filler metal supplied to the welding process is a mild steel. In an embodiment, the hardness as measured at the surface of the hardfacing ranges from 40 to 65 HRC. In an example, the iron-based hardfacing layer also includes tungsten carbide particles.

A forming method of an yttrium oxide fluoride (YOF) coating film and a (YOF) coating film formed thereby are disclosed. The YOF coating film has no or extremely small pores therein and a nanostructure to increase light transmittance thereof, and has high hardness and high bonding strength and thus can protect a transparent window of a display device. The method for forming an YOF coating film involves the steps of: providing pretreated YOF powder having a particle diameter ranging from 0.1 to 12 μm; receiving a transfer gas supplied from a transfer gas supply unit and receiving the pretreated YOF powder supplied from a powder supply unit to transfer the pretreated YOF powder in an aerosol state; and colliding/smashing (spraying) the pretreated YOF powder transferred in the aerosol state with/onto a substrate in a process chamber to form an YOF coating film on the substrate.

An Al-plated steel sheet includes: a steel sheet; an Al plating layer which is formed on one surface or both surfaces of the steel sheet and contains at least 85% or more of Al by mass %; and a surface coating layer which is laminated on the surface of the Al plating layer and contains ZnO and one or more lubricity improving compounds.

The invention relates to an aluminum alloy strip with improved surface optics, which is fabricated via hot and/or cold rolling, and consists of a type AA 3xxx, AA 5xxx, AA 6xxx or AA 8xxx aluminum alloy. The object of proposing an aluminum alloy strip that is suitable for attractive and precious surface optics despite the elevated percentage of alloy constituents is achieved in that, after degreasing, the finish-rolled aluminum alloy strip exhibits an increase in the luminance value L*(ΔL) in relation to the rolled-greasy state of more than 5 while measuring the color of the surface in the CIE L*a*b* color space using a standard illuminant D65 and a normal observation angle of 10°, excluding direct reflection in 45°/0° geometry.

High strength steel sheet having a tensile strength of 800 MPa or more comprising a middle part in sheet thickness and a soft surface layer arranged at one side or both sides of the middle part in sheet thickness, wherein each soft surface layer has a thickness of more than 10 μm and 30% or less of the sheet thickness, the soft surface layer has an average Vickers hardness of 0.60 time or less the average Vickers hardness of the sheet thickness ½ position, and the soft surface layer has a nano-hardness standard deviation of 0.8 or less is provided.

The present disclosure provides a multilayer coated cutting material having increased wear resistance at high temperatures, a method for manufacturing the same, and a cutting tool insert for mechanical machining including the same. According to an embodiment of the present disclosure, the multilayer coated cutting material includes a cemented carbide, cermet, ceramic, a cubic crystal boron nitride-based material or a hard alloy body of high-speed steel, and a cutting layer positioned on the base material and configured in multiple layers.

A hot-dip galvanized steel sheet wherein the hot-dip galvanized steel sheet comprises a base steel sheet and a hot-dip galvanized layer, a ferrite phase is, by volume fraction, 50% or less in a range of ⅛ thickness to ⅜ thickness centered at a position of ¼ thickness from the surface of the base steel sheet, a hard structure is 50% or more, wherein the hot-dip galvanized steel sheet has the hot-dip galvanized layer in which Fe is 5.0% or less and Al is 1.0% or less, and columnar grains formed of a ζ phase is 20% or more in an entire interface between the plated layer and the base steel sheet, on the surface of the base steel sheet in which a volume fraction of a residual austenite is 3% or less and a ratio of a volume fraction of the hard structure is 0.10 times or more to 0.90 times or less of that of the hard structure in the range of ⅛ thickness to ⅜ thickness in a range of 20 μm depth in a steel sheet direction originating an interface between the hot-dip galvanized layer and the base steel sheet, and wherein the hot-dip galvanized steel sheet has a refined layer at the side of the interface in the base steel sheet, and wherein an average thickness of the refined layer, an average grain size of ferrite in the refined layer and a maximum size of the oxide included in the refined layer are defined respectively.