Cutting silicon nitrides

Other ceramic cutting-tool materials include alumina, Si-Al-0-N, alumina-carbide composites and, more recently, a composite of silicon nitride reinforced with silicon carbide whiskers. This last material can be produced by chemical-vapor infiltration (CVI) and has high strength and toughness as shown in Table 18.3.Cl... 

Rebenne, H. E., and Bhat, D. G., Effect of Diffusion Interface on Adhesion and Machining Performance of TiN-Coated Silicon-Nitride Cutting Tools, Proc. ThirdInt. Conf. on Surface Modification Technologies, Neuchatel, Switzerland (Aug., 1989)... 

Among the useful compounds of silicon are silicon carbide (carborundum) and silicon nitride, which are hard, tough materials used for making cutting tools, abrasives, and engineering... 

Miao H, Qi, L, Cui G (1995) Silicon Nitride Ceramic Cutting-Tools and their Applications. In Low IM, Li XS (eds) Advanced Ceramic Tools for Machining Application - II Key Engineering Materials 114, Trans Tech Publications Ltd, Switzerland, p 135... 

In other useful applications, silicon nitride bearings have been found to offer excellent performance silicon nitride cutting tool inserts are a commercial product wear parts such as sand blast nozzles, seals, and die liners are also commercially produced the superior performance of heat exchangers has been demonstrated and there are also military applications. 

Silicon nitride whiskers are also produced by variations of processing conditions in these S3mthesis methods. Silicon nitride is used for toolbits for cutting cast iron and other high-temperatm% wear parts including burner nozzels. 

The practical utilization of silicon carbide and silicon nitride ceramics or of SiAlON in the above-mentioned application sectors has steadily increased in recent years. Ca. 400 t/a of SN-powder is currently consumed in the manufacture of SN-components. The main applications are for cutting tools, roller bearings, dosing and deliver pipes for aluminum processing, as well as a multiplicity of other components which enjoy the advantages of SN-ceramics. 

Significant recent changes in the market shares of the different kinds of cutting ceramics shown in Table 1 should be noted. There has been an increase in the use of ceramic cutting tools, attributed to increasing use of silicon nitride tools. 

Over the past decade a continuous increase in the number of application fields has been observed. Besides parts for the automotive industry (cam rollers, valve plates for common rail systems), which have not been produced in the volume that was predicted 10 years ago, applications such as cutting tools, ball bearings, wear parts, applications at high temperatures, and application in the electronic industry are becoming increasingly important [1-4]. A new cooking system based on a silicon nitride plate is penetrating into the market at the moment [5j. 

The excellent wear properties of silicon nitride materials are the basis for many applications of these materials, such as ceramic or hybrid rolling bearings, cutting tools, wear parts in automotive engines (valves, cam rollers, valve plates for eommon rail systems), and parts for metal shaping. 

R. D. Nixon and P. K. Mehrotra, Optimization of Sintering Aids in Silicon Nitrides for Cutting Tool Application , Ceramic Engineering < Science Proceedings, 18, 1997, 457-464. 

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