Abstract: An object of the invention is to provide a high-quality soldering method, by reducing, to a vacuum, the pressure in a vacuum room (2) in which a workpiece (10) having solid solder placed thereon consisting solely of tin or including tin and one or more components selected from silver, lead, copper, bismuth, indium and zinc is disposed. A free-radical gas is generated to remove an oxide film on the solder, and, after that, the generation of the free-radical gas is stopped, and the temperature of the solder is raised to a temperature above the melting point of the solder to melt the solder in the non-oxidizing atmosphere.

Abstract: A resin tank includes a tank body, a pipe sealing member and a pipe. The tank body reserves a liquid and is made of resin. Also, the tank body has at least a circular hole that connects with an inside of the tank body. The pipe sealing member is closely fitted into the circular hole. The pipe is installed in the pipe sealing member.

Abstract: Conventionally, heat treatment was necessary in the final stage of producing nodular cast iron products to give the nodular cast iron with desired mechanical properties. This was necessary because of the loss of graphitization capability of the molten metal when it is being formed into nodular cast iron during the process of spheroidization, and the heat treatment is therefore required to decompose cementite formation and thereby promote graphitization. The process of producing nodular cast iron according to the present invention can achieve the promotion of graphitization and the increase in the number of graphite nodules, which are both important for the production of high-quality thin-shell cast iron products, through the synergetic effect of processing the molten metal with a graphitization agent such as SiC or CaC.sub.2 and of adding a graphite atomization agent such as Bi.

Abstract: A brake member integrally cast from a single melt and composed of a sliding portion and a hub portion, the sliding portion having a flaky graphite cast iron microstructure with a good damping capacity and the hub portion having a high-strength cast iron microstructure. The sliding portion which may be a drum or a rotor has a damping capacity Q.sup.-1 of higher than 16.times.10.sup.-3. It is manufactured by pouring a melt having a hyper-eutectic flaky graphite cast iron composition into a cavity of a sand mold in which a chiller is embedded adjacent to a cavity region for the hub portion.

Abstract: A method of producing a nodular graphite cast iron having high strength and toughness in shorter time and with reduced production cost. The method comprises the following steps: rapidly cooling the casting, which has been removed from the mold at a predetermined temperature above the A.sub.1 transformation point, at such a cooling rate as not to permit the generation of pearlite structure, after having been held for a predetermined time within the austenite temperature range or immediately after having been removed from the mold; once stopping the rapid cooling at a temperature above the Ms point; slowly cooling the casting within a temperature range above the Ms point for a predetermined time or holding the casting at a constant temperature within a predetermined temperature range above the Ms point for a predetermined time; and cooling the casting slowly down to the normal temperature.