Abstract: The present invention relates to an apparatus, method, and reference sample for searching for molding conditions of an additive manufacturing apparatus based on a powder bed fusion method, and provides a search apparatus, a search method, and a reference sample that are remarkably more efficient and accurate than conventional counterparts. The reference sample for searching for the molding conditions is shaped so that it has a surface having aggregated punched holes formed by straight lines and curved lines involved in a fill region of a molding region (in-skin), a region for forming an overhang (down-skin), and a region for forming an outermost surface in the direction of molding height (up-skin). Slice data of the reference sample has at least two independent regions in an optional layer at a center in a lamination direction, and includes a small region and a large region. The small region has a width of 1 mm or less and is cut off from the outer edge of the reference sample.

Abstract: An evaluation method of residual stress in water jet peening includes a step of creating an analytical model including meshes according to a water jet peening (WJP) object, the shape of a nozzle, and an injection distance, a step of inputting WJP execution conditions, a step of calculating the internal pressure pBi of a cavitation bubble and a bubble number density ngi through jet flow analysis for a jet flow jetting from the nozzle, a step of calculating cavitation energy according to the internal pressure pBi of a cavitation bubble and a bubble number density ngi (S4), a step of calculating the burst energy of cavitation bubbles from the cavitation energy C, and a step of calculating the compressive residual stress of the WJP object from the collapse pressure of cavitation bubbles. Accordingly, the residual stress of the WJP object can be evaluated precisely in a shorter time.

Abstract: An evaluation method of residual stress in water jet peening includes a step of creating an analytical model including meshes according to a water jet peening (WJP) object, the shape of a nozzle, and an injection distance, a step of inputting WJP execution conditions, a step of calculating the internal pressure pBi of a cavitation bubble and a bubble number density ngi through jet flow analysis for a jet flow jetting from the nozzle, a step of calculating cavitation energy according to the internal pressure pBi of a cavitation bubble and a bubble number density ngi (S4), a step of calculating the burst energy of cavitation bubbles from the cavitation energy C, and a step of calculating the compressive residual stress of the WJP object from the collapse pressure of cavitation bubbles. Accordingly, the residual stress of the WJP object can be evaluated precisely in a shorter time.

Abstract: A method for executing water jet peening for giving an impact force to a surface of a structure member by a crushing pressure of a water jet and cavitation and improving residual stress, or washing, or reforming said surface, wherein said water jet peening is executed so as to make a natural frequency of oscillation of said structure member and a excitation frequency of oscillation of water jet peening different from each other.

Abstract: A method for executing water jet peening for giving an impact force to a surface of a structure member by a crushing pressure of a water jet and cavitation and improving residual stress, or washing, or reforming said surface, wherein said water jet peening is executed so as to make a natural frequency of oscillation of said structure member and a excitation frequency of oscillation of water jet peening different from each other.

Abstract: In a method for heat treatment of an existing pipe constituting a piping system, for converting the residual stress at a welded metallic portion and a welding heat influenced portion of the inside surface of the pipe, into a compressive stress and thereby generate the compressive stress in the inside surface of the existing pipe, a coolant is retained in the pipe; an arbitrary portion of the outside surface of the pipe is heated; thereby a temperature distribution little in temperature difference is produced in the wall surface of the pipe at the heated portion; and then the coolant is allowed to flow. By converting the residual stress at the welded metallic portion and the welding heat influenced portion of the inside surface of the pipe, into the compressive stress, stress corrosion cracking generated from the welded metallic portion and the welding heat influenced portion can be suppressed.

Abstract: There is provided an apparatus for picking up a defective portion replica that can pick up a replica with high accuracy and positively even from a surface of a structure in the water. Within a container part provided at a leading end of a replica pickup part is displaced a deformable member, such as a porous expansion member, which is excellent in adhesion with a replica and which deforms when a replica material is poured into a gap between a surface of a structure and the deformable member. The replica material from the replica material supply nozzle is poured into the gap between the surface of a structure and the porous expansion member and the replica is recovered by making use of adhesion with the porous expansion member.

Abstract: A method of producing naphthalenedicarboxylic acids by the oxidation of dialkyl-substituted naphthalene with a gas containing molecular oxygen in an organic solvent and in the presence of a catalyst comprising copper and bromine, or a catalyst comprising copper, bromine and at least one kind of element/compound selected from the group of consisting of amine compounds and heavy metallic elements which are vanadium, manganese, iron, nickel, palladium and cerium. And a method of producing diaryldicarboxylic acids by the oxidation of dialkyl-substituted diaryl compounds with a gas containing molecular oxygen in an organic solvent and in the presence of the same catalyst. These methods permit high yields of naphthalenedicarboxylic acids of high purity and of diaryldicarboxylic acids of high purity with the use of small amounts of catalyst.

Abstract: A method of producing naphthalenedicarboxylic acids by the oxidation of dialkyl-substituted naphthalene with a gas containing molecular oxygen under liquid phase conditions in an organic solvent and in the presence of a catalyst comprising copper and bromine, or a catalyst comprising copper, bromine and at least one kind of element/compound selected from the group of consisting of amine compounds and heavy metallic elements which are vanadium, manganese, iron, cobalt, nickel, palladium and cerium. And a method of producing diaryldicarboxylic acids by the oxidation of dialkyl-substituted diaryl compounds with a gas containing molecular oxygen in an organic solvent and in the presence of the same catalyst. These methods permit high yields of naphthalenedicarboxylic acids of high purity and of diaryldicarboxylic acids of high purity with the use of small amounts of catalyst.