Nickel-chromium boron alloys

Nickel-chromium-boron alloying coat applied on both punches and dies has been described and compared to untreated tools. Surprisingly, depending on the material under compression, the coating had the expected effect, or there was a total lack of effect, or they even increased ejection forces. The authors concluded that anyway, the tablets were superior in appearance. 

NICKEL-CHROMIUM-BORON ALLOYS PRODUCTION BY ALUMINOTHERMIC PROCESSES... 

Nickel-Chromium-Boron Alloys Production by Aluminothermic Processes. ..335... 

Choose material couples that are resistant to interaction in sliding (metal-to-metal wear resistance). Hardfacing alloys such as cobalt-base and nickel-chromium-boron alloys have been used for many years for applications involving metal-to-metal wear. Other surfaceengineering options include through-hardened tool steels, diffusion (case)-hardened surfaces, selective surface-hardened alloy steels, and some platings. 

Weld hardfacing coatings, for example, high-carbon iron-chromium alloys, tool steels, nickel-chromium-boron alloys, cobalt-base alloys, and austenitic manganese steels... 

Low-carbon, low-alloy steels are in widespread use for fabrication-welded and forged-pressure vessels. The carbon content of these steels is usually below 0.2%, and the alloying elements that do not exceed 12% are nickel, chromium, molybdenum, vanadium, boron and copper. The principal applications of these steels are given in Table 3.8. 

In recent years, the spraying process has been adapted for hard facing, using the chromium-nickel-boron alloys which have become known as Colmonoy. More recently still, the cobalt-base Stellite alloys have also been used. These materials in powder form are sprayed on to the surface in the usual way. The deposit is afterwards heat treated by a torch, so that fusion takes place. The process is often known as spray-welding. Such coatings are primarily used for hard facing under wear conditions, but as the Anal surface is nickel-chromium or cobalt-chromium they exhibit very high anticorrosive properties. 

Nicotine adenine dinucleotide phosphate (NADP+), 24 147 Nicotinic acid, 9 477-478 26 291 alkaloid precursor, 2 78 Ni-Cr alloys, 23 499. See also Nickel-chromium entries NiCrAlY coatings, 13 508 nido designation boranes, 4 184-186 boron hydrides, 4 170, 172-176 Nidrel, molecular formula and structure, 5 129t... 

Alloys are metallic substances containing two or more elements which are miscible when molten and do not separate when solidified. They may be liquid or solid. This mixture of elements, usually but not necessarily metals, allows careful manipulation of strength, melting point, corrosion resistance, magnetic, thermal, electrical, and other properties steel, for example, is an alloy of iron and carbon often present with nickel, chromium, copper, aluminium, boron, tungsten, manganese, cobalt, silicon, and other elements. 

Ferro-alloys Master alloys containing a significant amount of bon and a few elements more or less soluble in molten bon which improve properties of bon and steels. As additives they give bon and steel better characteristics (increased tensile sbength, wear resistance, corrosion resistance, etc.). For master alloy production carbothermic processes are used for large-scale ferro-sihcon, ferro-chromium, ferro-tungsten, ferro-manganese, ferro-nickel and metallothermic processes (mainly alumino and sihco-thermic) for ferro-titanium, ferro-vanadium, ferro-molybdenum, ferro-boron. 

Steel is an alloy containing chromium, manganese, molybdenum, nickel, vanadium and boron. Copper-nickel alloy, bronze and aluminium alloys are used in making coins. Fusible alloys having low melting points are used as solder and fuses in electrical circuits. 

Most of these are carbon-manganese-molybdenum alloys with small additions of chromium and/or nickel plus vanadium or niobium. Vanadium or niobium acts as a carbide stabilizer and grain refiner, improving both elevated temperature strength and notch ductility. An exception is Fortiweld (MOBO 45 is the same steel), which is a boron-treated 1/2% molybdenum steel. This alloy is the cheapest of the group, but has hardly been used for reactors in the U.K., possible because its impact properties in thick sections are not so attractive as alternative steels. 

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