Abstract: A process for producing an aluminum wheel includes a cleaning step, in which the surface of the aluminum wheel is chemically etched with an alkali cleaning liquid which contains an alkali builder, an organic builder, and a chelating agent to such an extent that the Si atomic ratio of metal Si to oxide Si is from 0.01 to 9, and a shot blast treatment step can be omitted for cleaning the surface of the aluminum wheel.

Abstract: A preform for a composite material which has high strength and excellent air permeability and hence is applicable to a high-speed die casting method and which is capable of forming a metal composite material having excellent mechanical properties by a high-speed die casting method. Also provided is a process for producing such a preform. Ceramic fibers or/and ceramic particles are mixed with a silica sol and calcium carbonate and sintered at a predetermined temperature to form a calcium/silicon sinter obtained from the silica sol and calcium carbonate. The calcium/silicon sinter coats the ceramic fibers or/and ceramic particles so that a preform having the fibers or/and the particles bound to each other by the calcium/silicon sinter is obtained. The preform for a composite material has high strength and excellent air permeability and is applicable to the high-speed die casting method capable of attaining high productivity.

Abstract: In a disc of an automobile wheel, a plurality of hub surface rounded portions are formed at intervals on an imaginary circle provided around a hub hole and centered on an imaginary center corresponding to the center of the hub hole. The hub surface rounded portions are provided with a compressive residual stress by a compression process for work hardening. The strength of the hub surface rounded portions can thus be improved.

Abstract: To propose an ultrasonic exploration method and an ultrasonic exploration apparatus that allow exploration of an exploration-target area such as a welded portion to provide a cross-sectional image of the exploration-target area accurately and stably. [Solution] An exploration operation, in which the transmission/reception position, at which ultrasonic waves are transmitted and received, is changed by a specified pitch distance, is performed for each of a plurality of incident angles. A nonlinear image in which echo signals acquired from harmonic waves of reflected waves are presented is generated for each incident angle. Each nonlinear image is converted into a frame conversion image in accordance with the cross-sectional shape of an exploration-target area. A signal intensity threshold for removing echo signals resulting from an orientation defect is determined in advance.

Abstract: The present invention proposes an automobile wheel that includes a wheel disk with improved stiffness to have increased strength and increased driving stability for lateral force. An imaginary inward angled line L is tangential to an inner circumferential surface 42a of an inward recessed circumferential portion 42 of a hat portion 24 and tangential to an inner circumferential surface 32a of a hub surface rounded portion 32 of a hub mounting portion 21. An imaginary outward angled line N is tangential to an inner circumferential surface 44a of an outward recessed circumferential portion 44 of the hat portion 24 and runs through an intersection point G of a disk flange 25 and an imaginary bottom line M. The imaginary bottom line M extends along a back side surface of the hub mounting portion 21.

Abstract: In an automobile wheel, a surface-side flange is provided on an outer circumferential edge of a wheel disk. The surface-side flange includes: a surface-side annular circumferential portion on an aesthetic surface; and a back-side annular circumferential portion that is formed continuously with, and on the back side of, the surface-side annular circumferential portion and that is thinner than the surface-side annular circumferential portion. An inner circumferential end of the back-side annular circumferential portion of the surface-side flange and an opening end of a surface-side bead seat of a wheel rim are welded together all along their circumferences. The automobile wheel allows the back-side annular circumferential portion of the surface-side flange to bear a stress that acts on a weld area. This relaxes the stress concentration on the weld area.

Abstract: To provide an arc start method in a consumable electrode type arc welding method capable of firmly executing arc start and capable of executing high quality high speed welding by restraining a welding defect from being brought about therefor, at a portion of a wire projected from a welding tip, a temperature of a front end portion of the wire is made to be at a temperature higher than a temperature of a portion thereof near the welding tip. The front end portion of the wire is preheated to 300° C. or higher, preferably, 450° C. or higher. The front end portion of the wire is preheated by generating arc for preheating. The preheating arc is generated in a spot-like shape at a position near a terminal end portion of a predetermined welding line by constituting a current lower than a welding current.

Abstract: A metal composite material is obtained by casting a melt of a metal and has an outer surface on which aluminum borate particles maintained in a porous form are exposed. Therefore, an oil is allowed to infiltrate the aluminum borate particles on the outer surface, to be retained therein and to ooze out during sliding. As a consequence, the sliding life during which desired sliding properties are maintained can be significantly prolonged. The metal composite material may be produced from a preform obtained by sintering aluminum borate particles covered with electrically neutralized silica and alumina particles which have been formed by mixing a silica sol and an alumina sol with aluminum borate particles in an aqueous solution to cover aluminum borate particles.

Abstract: An automobile wheel includes: a wheel rim 2 including a circumferential positioning fitting groove 32 formed circumferentially around the center axis of the wheel rim 2 in the front surface of a circumferential bent portion 31 at which a front bead seat portion 13 and a front rim flange portion 11 are formed continuously with each other; and a wheel disc 3 including a circumferential insertion edge 36 formed circumferentially around the center axis of the wheel disc 3 on the back surface of an outer peripheral edge portion 24. The wheel rim 2 and the wheel disc 3 are welded to each other for integration with the circumferential insertion edge 36 fitted in the circumferential positioning fitting groove 32. The respective center axes of the wheel rim 2 and the wheel disc 3 are aligned with each other with high precision, achieving an advantageous effect that vibration that occurs while an automobile is running is suppressed to improve the operation stability and achieve high durability.

Abstract: An object of the present invention is to obtain a vehicle wheel having a significant effect of preventing dirtying due to brake dust. A + (positively)-charged coating film in which the water contact angle is 35° or less and the product of saturated charging voltage (kV)×charge half life (sec) is 50 or less is formed on the surface of a vehicle wheel.

Abstract: A method of measuring a welding-groove position for an over-lapped fillet welding of thin members, comprising a projection step of projecting a slit light so that the slit light is projected on both the thin members crossing a welding-groove face, a two-dimensional image acquisition step of capturing the slit-light image projected on each of the thin members as two-dimensional images; a three-dimensional conversion step of converting the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter, and a calculation step of calculating the welding-groove position based on the three-dimensional data of the projected slit-light images, and relative positions between the projected slit-light images in the three-dimensional data defined by shapes and arrangement of the thin members.

Abstract: A tire/wheel assembly body enables reduction of road noise while reducing unsprung mass using a light-metal wheel. The tire/wheel assembly body is formed by installing a pneumatic tire on the light-metal wheel with a rigidity index (?) of 35 to 65 (1/rad). In the pneumatic tire, reinforcement layers are arranged at end portions of a belt layer.

Abstract: A metal composite material which can show high wear resistance and durability when used as a sliding member and a process for producing such a metal includes material are proposed. The metal composite material (10) comprises a porous preform (1) containing porous aluminum borate particles (3) in which pores (3a) of the aluminum borate particles (3) are filled with a metal as a result of impregnation of a melt of the metal into the porous preform under pressure. In the metal composite material (10), the metal base material and the aluminum borate particles (3) are tightly bound to each other. Therefore, the metal composite material (10) has high strength and hardness and can show excellent wear resistance when used as a sliding member.

Abstract: A mounting device for a rim disk of a full face wheel for a vehicle has a disk disposed on a rotating table rotated by a rotating device about the center axis (X) of a full face wheel and radially positioned by a hub hole fitting piece and a rim disposed on the disk and radially positioned by arresting a rim drop part by a rim position arresting means, with the disk and rim being pressingly held between a disk support piece and a rim support piece by upwardly pulling an aligning rod connected to the rotating table through a rod connection means along the center axis (X) of the full face wheel while downwardly pressing a rim flange part by the rim support piece to bring the disk and the rim into a pressed state. By the rim disk mounting device, the disk and the rim radially positioned with high accuracy can be brought into pressed state with a strong holding pressure, and both the disk and the rim can be stably rotated.

Abstract: A method of manufacturing a full face vehicle wheel having a high durability performance, in which the back surface of a wheel disk is provided in advance with an annular joining groove. A peripheral joining end of a wheel rim is provided in advance with an inside slope end surface. The peripheral joining end is seated and positioned on the bottom surface of the annular joining groove. A welding heat confining annular region is produced between the inside groove wall of the annular joining groove and the inside slope end surface. The annular joining groove and the peripheral joining end are joined by welding.

Abstract: A preform for a composite material which has high strength and excellent air permeability and hence is applicable to a high-speed die casting method and which is capable of forming a metal composite material having excellent mechanical properties by a high-speed die casting method. Also provided is a process for producing such a preform. Ceramic fibers or/and ceramic particles are mixed with a silica sol and calcium carbonate and sintered at a predetermined temperature to form a calcium/silicon sinter obtained from the silica sol and calcium carbonate. The calcium/silicon sinter coats the ceramic fibers or/and ceramic particles so that a preform having the fibers or/and the particles bound to each other by the calcium/silicon sinter is obtained. The preform for a composite material has high strength and excellent air permeability and is applicable to the high-speed die casting method capable of attaining high productivity.

Abstract: A mounting device for a rim disk of a full face wheel for a vehicle has a disk disposed on a rotating table rotated by a rotating device about the center axis (X) of a full face wheel and radially positioned by a hub hole fitting piece and a rim disposed on the disk and radially positioned by arresting a rim drop part by a rim position arresting means, with the disk and rim being pressingly held between a disk support piece and a rim support piece by upwardly pulling an aligning rod connected to the rotating table through a rod connection means along the center axis (X) of the full face wheel while downwardly pressing a rim flange part by the rim support piece to bring the disk and the rim into a pressed state. By the rim disk mounting device, the disk and the rim radially positioned with high accuracy can be brought into pressed state with a strong holding pressure, and both the disk and the rim can be stably rotated.

Abstract: A preform for the composite material and an aluminum composite material which can form a composite material has excellent abrasion resistant property and high strength and a manufacturing method of the same are disclosed. A pre-mixture 9 comprising aluminum borate whisker 3 and potassium titanate whisker 4 in the range of 5% to 20% by volume was sintered at certain temperature. The titanium oxide 11 produced by the whisker reaction was bound to the surface of aluminum borate whisker 3, and the preform having high strength was obtained accordingly. Aluminum composite material 10 having excellent abrasion resistant property and high strength was obtained by impregnating aluminum alloy 6 to preform 1 for composite material.

Abstract: To provide an arc start method in a consumable electrode type arc welding method capable of firmly executing arc start and capable of executing high quality high speed welding by restraining a welding defect from being brought about therefor, at a portion of a wire projected from a welding tip, a temperature of a front end portion of the wire is made to be at a temperature higher than a temperature of a portion thereof near the welding tip. The front end portion of the wire is preheated to 300° C. or higher, preferably, 450° C. or higher. The front end portion of the wire is preheated by generating arc for preheating. The preheating arc is generated in a spot-like shape at a position near a terminal end portion of a predetermined welding line by constituting a current lower than a welding current.