According to one aspect of the present invention, there is provided a hollow structure body having a hollow structure, in which a first shaped product constituted by a first fiber-reinforced resin material containing first reinforcing fibers and a first matrix resin and a second shaped product constituted by a second fiber-reinforced resin material containing second reinforcing fibers and a second matrix resin are combined, wherein in an arbitrary cross section in a direction perpendicular to an axial direction of the hollow structure, a ratio Sc/St between compressive strength Sc of a structure in the first shaped product and tensile strength St of a structure in the second shaped product satisfies formula (1):
(σc/σt)*(Hc/Ht)<(Sc/St)<(σt/σc)*(Hc/Ht)  formula (1).

A method of making an aluminum alloy-resin composite and an aluminum alloy-resin composite obtained by the same are provided. The method may comprise: S1: anodizing a surface of an aluminum alloy substrate to form an oxide layer on the surface, in which the oxide layer includes nanopores; S2: immersing the resulting aluminum alloy substrate obtained at step S1 in an alkaline solution having a pH of about 10 to about 13, to form corrosion pores on an outer surface of the oxide layer, wherein the alkaline solution is an aqueous solution including at least one selected from a soluble carbonates, a soluble alkali, a soluble phosphate, a soluble sulfate, and a soluble borate; S3: injection molding a resin onto the surface of the resulting aluminum alloy substrate in step S2 in a mold to obtain the aluminum alloy-resin composite.

A method of preparing aluminum alloy-resin composite and an aluminum alloy-resin composite obtained by the same are provided. of the method comprises: S1: anodizing a surface of an aluminum alloy substrate to form an oxide layer on the surface, the oxide layer including nanopores; S2: immersing the resulting aluminum alloy substrate obtained in step S1 in a buffer solution having a pH of about 10 to about 13, to form a corrosion pores on an outer surface of the oxide layer; and S3: injection molding a resin onto the surface of the resulting aluminum alloy substrate obtained in step S2 in a mold to obtain the aluminum alloy-resin composite.

A mechanical assembly for securing a first sheet to a second sheet includes a first projection having a first sidewall and a first top wall. The first sidewall extends from the first top wall at a first acute angle. The first sidewall includes a first top end and a first bottom end. A first discontinuity is defined in the first sidewall between the first top end and the first bottom end. A first base wall extends from the first bottom end. The first base wall extends generally parallel to the first top wall.

A mechanical assembly for securing a first sheet to a second sheet includes a first projection having a first sidewall and a first top wall. The first sidewall extends from the first top wall at a first acute angle. The first sidewall includes a first top end and a first bottom end. A first discontinuity is defined in the first sidewall between the first top end and the first bottom end. A first base wall extends from the first bottom end. The first base wall extends generally parallel to the first top wall.

The present invention provides a polypropylene-polyphenylene ether-polystyrene ternary alloy, including the following components in parts by weight: 100 parts of a polypropylene and a polyphenylene ether and a polystyrene, wherein the polypropylene accounts for 10% to 60%, the polyphenylene ether accounts for 10% to 60%, and the polystyrene accounts for 5% to 30%; 5 parts to 25 parts of a compatibilizer; and 10 parts to 60 parts of a polyphosphate compound. The polypropylene-polyphenylene ether-polystyrene ternary alloy of the present invention has an advantage of a less smoke release amount during melt.

A bonded body is formed of a first member and a second member. The first member has a first base portion and a first welded portion which protrudes from the first base portion toward the second member side. The second member has a second base portion and a second welded portion which protrudes from the second base portion toward the first member side. In a first region of the joint portion, a first rib formed so as to project from the first base portion toward the second member side covers the first welded portion and the second welded portion from the side. In a second region different from the first region, a second rib formed so as to project from the second base portion toward the first member side covers the first welded portion and the second welded portion from the side.

A bonded body is formed of a first member and a second member. The first member has a first base portion and a first welded portion which protrudes from the first base portion toward the second member side. The second member has a second base portion and a second welded portion which protrudes from the second base portion toward the first member side. In a first region of the joint portion, a first rib formed so as to project from the first base portion toward the second member side covers the first welded portion and the second welded portion from the side. In a second region different from the first region, a second rib formed so as to project from the second base portion toward the first member side covers the first welded portion and the second welded portion from the side.

There is provided a method for producing a metal-resin composite which includes a resin member and a metal member having a roughened surface in at least a portion of the surface thereof, the resin member being joined so as to be in contact with at least a portion of the roughened surface. The method includes a step of joining the resin member and the metal member by melting the resin member with the frictional heat generated in the surface of the metal member on its side opposite to the resin member in a state where the metal member and the resin member are superposed. The method includes making adjustment so that when the roughened surface is measured at arbitrary five points by using a confocal microscope according to ISO 25178, the developed area ratio (Sdr) is 5 or more in terms of number-average value.

There is provided a method for producing a metal-resin composite which includes a resin member and a metal member having a roughened surface in at least a portion of the surface thereof, the resin member being joined so as to be in contact with at least a portion of the roughened surface. The method includes a step of joining the resin member and the metal member by melting the resin member with the frictional heat generated in the surface of the metal member on its side opposite to the resin member in a state where the metal member and the resin member are superposed. The method includes making adjustment so that when the roughened surface is measured at arbitrary five points by using a confocal microscope according to ISO 25178, the developed area ratio (Sdr) is 5 or more in terms of number-average value.