Abstract: A process prevents a reduction in the strength of the joint between the liner components, and assures high productivity without impairment. The peripheral walls (6, 7) of the liner component (4) and each of the second liner components (5) are brought into contact with each other, a probe (22) of friction agitation joining tool (20) is placed into the two liner components across the contact portions thereof, and the probe (22) in rotation is thereafter moved relative to the two liner components (4, 5). Assuming that the number of revolutions of the probe (22) is R rpm and that the speed of joining of the two liner components (4, 5) is V mm/min, R/V is in the range of 2?R/V?12.

Abstract: A tubular metal body 1 comprises a tube 2 extruded through a porthole die and composed of a plurality of components 2b joined to one another with a plurality of joint portions 2a extending over the entire length of the tube. The base material metal of the extruded tube 2 in each of the joint portions 2a is subjected to a modifying treatment to produce finely divided crystal grains. The modifying treatment for the extruded tube 2 is conducted preferably by frictionally agitating each joint portion using a probe 8 of a friction agitation joining tool 6. The tubular metal body 1 is available with an increased length in a larger size and has high pressure resistance.

Abstract: A pressure vessel liner includes a tubular trunk, and head plates for closing opposite end openings of the trunk. Provided inside the trunk is a reinforcing member integral with the trunk and extending longitudinally of the trunk for dividing the interior of the trunk into a plurality of spaces. The two head plates are joined respectively to opposite ends of the reinforcing member. The pressure vessel liner has an enhanced pressure resistant strength against longitudinal forces.

Abstract: A filler wire for laser-welding an aluminum alloy is described, which comprises a base material of Aluminum-Silicon based alloy and a flux of Aluminum-Potassium-Fluorine-based composition. The amount of the flux in the base material is greater than 0 (zero) wt. % and less than approximately 1.0 wt. %.

Abstract: A filler wire for laser-welding an aluminum alloy is described, which comprises a base material of Aluminum-Silicon based alloy and a flux of Aluminum-Potassium-Fluorine-based composition. The amount of the flux in the base material is greater than 0 (zero) wt. % and less than approximately 1.0 wt. %.

Abstract: An aluminum-copper clad member includes an aluminum-base member, a copper-base member and an insertion member made of pure aluminum or JIS A1xxx series aluminum alloy. The aluminum-base member and the copper-base member are clad via the insertion member. A heat sink includes a heat radiation portion made of aluminum-base material and provided with a plurality of tongue-like fins formed by skiving a surface layer of one side of the heat radiation portion and a thermal diffusion portion made of copper-base material and joined to the other side of the heat radiation portion via an insertion member made of pure aluminum or JIS A1xxx series aluminum alloy.

Abstract: A process for producing a flat heat exchange tube having opposed upper and lower walls and a plurality of reinforcing walls connected by brazing between the respective upper and lower walls for dividing the tube interior into parallel fluid passages. In order to strengthen the brazed connection between the reinforcing walls and the lower surface of the upper wall and to prevent the creation of a clearance space therebetween, the lower surface of the upper wall is provided in advance with longitudinally extending ridges with which the upper surfaces of the reinforcing walls come in contact to eliminate the clearances and thus insure the existence of a continuous brazed connection between each reinforcing wall and lower surface of the upper wall.

Abstract: An aluminum alloy brazing agent containing a flux is made by compacting a powder mixture of a matrix powder and a flux powder at a first temperature so as to form a rigid piece, and then conducting a secondary forming of the rigid piece into a desired shape at a second temperature. The first temperature is lower than 480.degree. C., preferably lower than 400.degree. C., and more preferably room temperature, so that the compacting may be conducted in the air. The second temperature is 300.degree.-575.degree. C. for the secondary forming, which also may preferably be conducted in an non-oxidizing atmosphere, so that the brazing agent can be of an improved capability of brazing aluminum articles and be produced inexpensively.

Abstract: A method is provided to braze aluminum materials to each other, the method comprising a step of producing a fluoride gas-containing atmosphere within a brazing oven. The method further comprises a step of brazing the aluminum materials, by heating said materials within said atmosphere melts. The fluoride gas-containing atmosphere is produced in the soldering oven: by introducing an inert gas and the fluoride gas through different passages; by introducing into the oven a mixture of the inert gas and the fluoride gas; or by heating a fluoride in a receptacle which is placed in the oven so as to gasify the fluoride within the oven.

Abstract: A flux for brazing is prepared from 31.5% to 56.2% of KF and 68.5% to 43.8% of at least one of .UPSILON.-AlF.sub.3 and finely divided .beta.-AlF.sub.3. The KF is dissolved in water, and the AlF.sub.3 is then placed into the resulting KF aqueous solution to react the KF with the AlF.sub.3. The reaction product is dried.