Provided is a hot rolled steel sheet comprising a predetermined composition wherein the hot rolled steel sheet comprises first ferrite with an average orientation difference in the same grain of 0.5 to 5.0° in 30 to 70 vol %, at least one type of structures among bainite and second ferrite with an average orientation difference of 0 to less than 0.5° and the first ferrite in a total of 95 vol % or more, a balance microstructure of 5 vol % or less, has an average grain size of the first ferrite of 0.5 to 5.0 μm, and has an average grain size of the other structures of 1.0 to 10 μm. Provided is a method for producing a hot rolled steel sheet comprising rolling where two or more consecutive passes of rolling including a final pass are performed under conditions of a rolling temperature: A point or more and less than Ae.sub.3 point etc., and where a total strain amount of all passes satisfying the conditions is 1.4 to 4.0, cooling by a 20 to 50° C./sec average cooling rate, and coiling the steel sheet at 300° C. to 600° C.

A metal laminate includes a lamination of a first metal plate and a second metal plate. The first metal plate includes a caulking that exhibits a mountain shape protruding from a back surface side and recessed on a front surface side, and the second metal plate includes an accommodating portion configured to accommodate the caulking such that the caulking is fitted to the accommodating portion. The caulking includes a recessed portion provided on an inner concave surface of the caulking and recessed toward the back surface side of the first metal plate, and an abutting portion provided on an outer convex surface of the caulking and abutted against an inner surface of the accommodating portion at a position corresponding to the recessed portion. The abutting portion expands laterally from the outer convex surface toward the inner surface of the accommodating portion.

A nickel-based alloy composition consisting, in weight percent, of: between 1.0 and 3.5% aluminium, 0.0 and 3.6% titanium, 0.0 and 6.0% niobium, 0.0 and 4.9% tantalum, 0.0 and 5.4% tungsten, 0.0 and 4.0% molybdenum, 8.9 and 30.0% cobalt, 10.8 and 20.6% chromium, 0.02 and 0.35% carbon, between 0.001 and 0.2% boron, between 0.001 and 0.5% zirconium, 0.0 and 5.0% rhenium, 0.0 and 8.5% ruthenium, 0.0 and 4.6 percent iridium, between 0.0 and 0.5% vanadium, between 0.0 and 1.0% palladium, between 0.0 and 1.0% platinum, between 0.0 and 0.5% silicon, between 0.0 and 0.1% yttrium, between 0.0 and 0.1% lanthanum, between 0.0 and 0.1% cerium, between 0.0 and 0.003% sulphur, between 0.0 and 0.25% manganese, between 0.0 and 6.0% iron, between 0.0 and 0.5% copper, between 0.0 and 0.5% hafnium, the balance being nickel and incidental impurities, wherein the following equations are satisfied in which W.sub.Nb, W.sub.Ta, W.sub.Ti, W.sub.Mo, W.sub.Al, W.sub.Re and W.sub.Ru are the weight percent of niobium, tantalum, titanium, molybdenum, aluminium, rhenium and ruthenium in the alloy respectively 4.2≤(W.sub.w+0.92 W.sub.R.sub.e+1.58 W.sub.Ru) W.sub.Mo, W.sub.Al+CO 0.5 W.sub.Ti+0.3 W.sub.Nb+0.15W.sub.Ta≤4.0 and 3.0≤W.sub.Al+0.5W.sub.Ti+1.5(0.3W.sub.Nb+0.15W.sub.TA).

A peening method which can sufficiently improve fatigue properties of a lap fillet welded joint having a thin steel sheet as a base sheet, in which a knocking pin having a predetermined shape is continuously knocked as a series of knocking toward a direction inclined relative to the welding direction, the series of knocking is repeatedly performed in the welding direction, at that time, a knocking mark group made of a plurality of knocking marks formed by the series of knocking is superimposed on at least a part of an adjacent knocking mark group while an end part in the direction orthogonal to the welding direction of the knocking mark group is separated from an end part in the direction orthogonal to the welding direction of the adjacent knocking mark group.

A peening method which can sufficiently improve fatigue properties of a lap fillet welded joint having a thin steel sheet as a base sheet, in which a knocking pin having a predetermined shape is continuously knocked as a series of knocking toward a direction inclined relative to the welding direction, the series of knocking is repeatedly performed in the welding direction, at that time, a knocking mark group made of a plurality of knocking marks formed by the series of knocking is superimposed on at least a part of an adjacent knocking mark group while an end part in the direction orthogonal to the welding direction of the knocking mark group is separated from an end part in the direction orthogonal to the welding direction of the adjacent knocking mark group.

An acoustic panel is provided that includes a perforated first skin, a second skin and a corrugated structure. The corrugated structure is between and is connected to the perforated first skin and the second skin. The corrugated structure includes a first baffle, a first septum, first material and second material that is configured with the first material. The first baffle is formed by an uninterrupted portion of the first material. The first septum is formed by a portion of the second material that is exposed through an interruption in the first material.

A thermal insulation system for an aerospace duct through which high temperature fluid, greater than 500 F, passes. The thermal insulation system can experience pressures less than 80 kilopascals and can be included in a turbine engine. The thermal insulation system includes at least a first foil layer confronting the duct, an insulation layer confronting the first foil layer, a second foil layer confronting the insulation layer, and at least one coating applied to any one of the layers.

An adjustable deforming composite structure based on a hydrogen-induced expansion effect and a preparation method therefor are provided. The hydrogen-induced expansion effect means metals absorb hydrogen under a hydrogen-containing atmosphere and at a temperature to produce a volume expansion effect. Reactions between the metals and hydrogen are reversible reactions. When a hydrogen partial pressure is reduced or the temperature is increased, the hydrogen in the metals is removed, and the metals are restored to an original shape. Under a stimulation of external hydrogen and heat, a composite of a hydrogen-absorbing metal and other non-hydrogen-absorbing materials undergo an adjustable deformation according to a design, and a material undergoes reversible shape changes. The preparation method is applied to composite materials for a 4D printing and is used for an intelligent shape adjustment at a medium to high temperature.

A composite sandwich panel assembly including an open area core, a high gloss surface sheet, and a structural skin. The open are core defines a plurality of pores and has a first face and an opposing second face. The high gloss surface sheet is adhered to the first face of the open area core by a first adhesive layer. The high gloss surface sheet has a high gloss surface. The structural skin is adhered to the second face of the open area core by a second adhesive layer. A process for forming the composite sandwich panel assembly includes positioning the high gloss surface sheet, joining the first face of the open area core to the high gloss surface sheet with a first adhesive layer intermediate therebetween, and joining the structural skin to the second face of the open area core with a second adhesive layer intermediate therebetween.

The present disclosure provides a solar reflecting film and a preparation method thereof. The solar reflecting film includes a substrate and a functional layer stacked on each other. The functional layer includes a first reflecting layer, a barrier layer, and a second reflecting layer stacked on the substrate in order. The barrier layer includes a first barrier layer and a second barrier layer stacked on the first barrier layer. The first barrier layer is metal fluoride, inorganic non-metallic oxide, metal oxide or a combination thereof. The second barrier layer is metal oxides, metal nitrides, semiconductor doped compounds or a combination thereof. And a material of the first barrier layer is at least partially different from that of the second barrier layer.