Fabrication brazing

The solder and ahoy market, including low melting or fusible ahoys, is a principal user of indium (see SoLDERS AND BRAZING ALLOYS). The addition of indium results in unique properties of solders such as improved corrosion and fatigue resistance, increased hardness, and compatibhity with gold substrates. To fachitate use in various appHcations, indium and its ahoys can be easily fabricated into wine, ribbon, foil, spheres, preforms, solder paste, and powder. 

GR-6.2.2.5 Construction Plan. The processes of construction shall include procedures for fabrication, assembly, handling, storage and preservation, forming, and erection, in addition to the special processes of welding, brazing, heat treating, and postweld heat treating. 

Requirements for vessels fabricated by forging in Part UF include unique design requirements with particular concern for stress risers, fabrication, heat treatment, repair of defects, and inspection. Vessels fabricated by brazing are covered in Part UB. Brazed vessels cannot be used in leth service, for unfired steam boilers, or for direct firing. Permitted brazing processes as well as testing of brazed joints for strength are covered. Fabrication and inspection rules are also included. 

The cross or transverse thread in a fabric or other textile structure. 3) A metal or alloy used in brazing and soldering lo effect union nf the metals being joined. 

Apparatus in which fluorine is to be handled at room temperature may be made from a number of metals. Platinum, copper, nickel, magnesium, monel metal, brass, steel, and German silver are all known to be satisfactory. Most of these become coated with a film of fluoride which prevents further corrosion. If the metal is in contact not only with fluorine but also with a liquid such as water or hydrogen fluoride, corrosion frequently becomes troublesome. Under such circumstances, platinum usually behaves in the most satisfactory manner. With the gas alone, brass needle valves may be used with success, but the packing is eventually ruined. Fabrication of apparatus is best accomplished by welding, brazing, or silver soldering. Solder made from lead and tin does not resist attack. 

Membranes for pressure and flux testing were mounted, using a brazing process developed at ANL, within four inch long, 0.75 in. O.D., heavy-wall, Iconel 600 tubing which had been machined to form a small seat to accommodate the membrane. Typically, the membrane diameter was 0.69 in. (17.5 mm.). Unmounted membranes of the same composition, as well as membranes of varying Ni content, were also available for characterization studies. Because the pressure tested membranes had to be pre-mounted, the before-and-after characterization studies refer to membranes of the same composition and fabrication, but not the same physical membranes. 

For Pq2 > Pq2(M) (see Figure 6.11), an oxide skin is formed at the metal surface, inhibiting the movement of the triple line. Because this phenomenon is very important in the processing of interfaces in multimaterials or in brazed-joint fabrication, it will be discussed in detail in this sub-section. 

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