CUTTING AND GRINDING TOOLS

The three requirements of a cutting or grinding tool material are hardness, tou mess, and chemical stability. The refiactory carbides and 

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Composites. Another type of electro deposit in commercial use is the composite form, in which insoluble materials are codeposited along with the electro-deposited metal or alloy to produce particular desirable properties. Polytetrafluoroethylene (PTFE) particles are codeposited with nickel to improve lubricity (see Lubrication and lubricants). SiHcon carbide and other hard particles including diamond are co-deposited with nickel to improve wear properties or to make cutting and grinding tools (see Carbides Tool materials). 

The nitrides reviewed here are those which are commonly produced by CVD. They are similar in many respects to the carbides reviewed in Ch. 9. They are hard and wear-resistant and have high melting points and good chemical resistance. They include several of the refractory-metal (interstitial) nitrides and three covalent nitrides those of aluminum, boron, and silicon. Most are important industrial materials and have a number of major applications in cutting and grinding tools, wear surfaces, semiconductors, and others. Their development is proceeding at a rapid pace and CVD is a major factor in their growth. 

The refractory carbides are hard and wear resistant, have high melting points, and are chemically inert. In a relatively short time, they have become major industrial materials with numerous applications such as cutting and grinding tools, bearings, textile-machinery components, oxidation-resistant gas burners, and many others. 

The refractory nitrides are in many respects similar to the refractory carbides. They are hard and wear-resistant with high melting points and good chemical resistance. They are important industrial materials and have a significant number of major applications in cutting and grinding tools, wear surfaces, semiconductors, and others. 

This chapter is a review of the applications of refi tory carbides and nitrides in each of the following industrial cat ories automotive and aerospace, industrial machinery and equipment, cutting and grinding tools, armor, nuclear, semiconductor, and optical. 

Besides being one of the hardest known substances, diamond is also highly resistant to corrosion and is stable to exceptionally high temperatures. At present, commercial diamonds are widely used to strengthen cutting and grinding tools. These diamonds are embedded in the tools and are not intimately and uniformly part of the material. 

Poly(alkylene glycol)s are also used as lubricity additives ia water-based synthetic cutting and grinding fluids (36), and ia aqueous metalworking fluids. Under the high frictional heating at the tool or die contact with the workpiece, the polyalkylene glycol comes out of solution ia fine droplets which coat the hot metal surfaces. 

Fine particles removed by a cutting or grinding tool. Metal swarf means turnings, borings, chips, wires, clippings, and foil. 

The three requirements of a cutting or grinding tool material are hardness, toughness, and chemical stability. Diamond meets the first since it isthe hardest material. However, it is inherently brittle, haslowtoughness, and reacts readily with carbide-forming metals, thus limiting its use. 

Uses Surfactant, film-former in metalworking applies., esp. for aluminum cutting and grinding and in fiber and plastic lubrication Features Reacts readily with alkalinity sources, making it easily incorporated into water-based fluids when exposed to temps, common in metal-forming operations, its film-forming props, reduce heat and improve tool life Properties SI. yel. cl. liq. sp.gr. 1.018 vise. 510 cp pH 2.4 (10%) 3.79% P UseLevei 1-15%... 

Because rhenium is very difficult to machine with carbide tools and other conventional methods, electrical-discharge machining (EDM), electrochemical machining (ROM), abrasive cutting, or grinding is... 

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