| 摘要 |
A nickel-chromium-based brazing alloy has a composition consisting essentially of about 9.5 to about 16.5 atom percent chromium, 0 to about 5 atom percent iron, about 10 to about 15 atom percent silicon, about 6 to less than 7 atom percent boron, and 0 to about 5 atom percent molybdenum, the balance being essentially nickel and incidental impurities. The alloy is especially suited for use as a brazing filler metal for joining stainless steel and/or superalloy at temperatures above 1100 degree(s) C. Such a filler metal has a thickness ranging from about 65 to 100 micrometers and a width ranging from 100 to 250 millimeters and more. Honeycomb structures and thin corrugated fin/plate structures particularly suited for use in manufacture of plate-type heat exchangers formed at least in part from stainless steels and/or superalloys are brazed using a unique process. The process is characterized by a long holding time at brazing temperature, and combines brazing and diffusion annealing in one technological step. Brazements produced by the process exhibit complete disappearance of central eutectic line and brittle intermetallic compounds from the joint microstructure. The brazements further exhibit joint ductility, as well as high strength and fatigue and corrosion resistance.
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