Abstract: Provided is a polishing composition capable of polishing a layer containing an element in group 13 of the periodic table in a content of 40 mass % or more at a high polishing speed while reducing surface defects due to polishing. Provided is a polishing composition for use in polishing an object to be polished having a layer containing an element in group 13 of the periodic table in a content of 40 mass % or more, the polishing composition containing a cationically modified silica, a trialkylamine oxide, and an oxidizing agent, wherein the content of the trialkylamine oxide is 3 mass ppm or more and 40 mass ppm or less with respect to the total mass of the polishing composition, and the pH is less than 5.

Abstract: Disclosed is a method for manufacturing a honeycomb structure. The method includes molding a molded body from a mixture containing silicon carbide particles, an organic component, and a dispersion medium, removing the organic component included in the molded body to obtain a porous honeycomb body, and impregnating an inner portion of partition walls of the porous honeycomb body with metal silicon. In a state in which the porous honeycomb body is placed on a support inside a container containing solid metal silicon, the impregnating an inner portion of the partition walls is performed by heating the inside of the container to a temperature higher than or equal to a melting point of the metal silicon so that the porous honeycomb body is impregnated with molten metal silicon through the support that is porous.

Abstract: Provided is a means capable of sufficiently removing organic residues on the surface of an object to be polished after polishing. A surface treatment composition includes a polymer having a building block represented by Formula (1) in [Chemical Formula 1], a chelating agent, and water and is used to treat the surface of an object to be polished after polishing, and the chelating agent has at least one of a phosphonic acid group and a carboxylic acid group. In Formula (1), R1 is a hydrocarbon group having 1 to 5 carbon atoms; and R2 is a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

Abstract: Provided is a means capable of sufficiently removing organic residues on the surface of an object to be polished after polishing. A surface treatment composition includes a polymer having a building block represented by Formula (1) in [Chemical Formula 1], a chelating agent, and water and is used to treat the surface of an object to be polished after polishing, and the chelating agent has at least one of a phosphonic acid group and a carboxylic acid group. In Formula (1), R1 is a hydrocarbon group having 1 to 5 carbon atoms; and R2 is a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

Abstract: The polishing composition according to the present invention is a polishing composition which contains abrasive grains, an additive, a pH adjusting agent, and a dispersing medium and in which a zeta potential of the abrasive grains is negative, the additive is a crosslinked bicyclic compound having a tertiary nitrogen atom, a content of the additive is more than 0% by mass and less than 0.5% by mass with respect to the entire polishing composition mass, and a pH of the polishing composition is less than 5.

Abstract: Disclosed is a method for manufacturing a honeycomb structure. The method includes molding a molded body from a mixture containing silicon carbide particles, an organic component, and a dispersion medium, removing the organic component included in the molded body to obtain a porous honeycomb body, and impregnating an inner portion of partition walls of the porous honeycomb body with metal silicon. In a state in which the porous honeycomb body is placed on a support inside a container containing solid metal silicon, the impregnating an inner portion of the partition walls is performed by heating the inside of the container to a temperature higher than or equal to a melting point of the metal silicon so that the porous honeycomb body is impregnated with molten metal silicon through the support that is porous.

Abstract: Disclosed is a heat exchanger that includes first cells through which a first fluid flows, second cells through which a second fluid flows, and partition walls that partition the first cells and the second cells. The heat exchanger exchanges heat between the first fluid and the second fluid. The partition walls include a frame portion having silicon carbide as a main component and a filling portion that covers a surface of the frame portion and is formed from a metal that fills a void in the frame portion. The partition walls have a surface roughness Ra of 1.0 ?m or greater.