1、附录 A 外文翻译 原文: Putting Ceramic Tool to Rational Use -W. C. Ye, F. Zhou, Huaiyin Institute of Industrial Engineering Abstract: Ceramic tool is one of main cutting tools for processing precisely. Because of its excellent performance and high ratio of property to price, it is in users good grace. This p
2、aper introduces the types of domestic cutting tool material, the choice of name and the methods of making rational use. Keywords: Ceramic tool; Duration of cutter; Use Ceramic tool is one of main cutting tools for processing precisely. Owing to the high hardness of ceramic(91-95HRA)and good wear-res
3、istance that is four times higher than that of cemented carbides, the duration of ceramic tool is several to tens times as long as cemented carbide tools. Ceramic can maintain higher hardness(80HRA)at temperatures as high as 1200 J and therefore can be used at much high temperatures. In has small af
4、finity, low friction coefficient, high bonding resistance , proliferating resistance and less tendency to form a built-up edge, all of these make it possible to get good machined surface quality, while its price is far less than diamond tools and CBN cutting tools whose machinability is similar to i
5、t. Besides of general cast irons and steels, it can also machine of low machinability steels such as hardened-steel, high strength steel, chilled iron and nickel-base alloy. In addition, it can also be used with turning and milling instead of grinding to promote produce efficiency. However, ceramic
6、tool has the disadvantages of lower strength and higher brittleness, so it has been mainly used in precise processing for a long time. In all sorts of cutting tool material, it occupied less proportion. In recent years, due to successful control of raw material pureness and grain dimension, adding c
7、arbide and metal, adopting hot press process(HP)and hot isostatic process (HIP), not only bending strength is improved to 0.9 to 1 GPa(even up to 1.3 to 1.5 GPa, equivalent to cemented carbides), but also its fracture toughness and shockresistance are quite improved, so its use range is expanded day
8、 by day. Besides of general finishing and semi-finishing, it can be used in roughing. In addition, it is available in turning, milling and planning, so ceramic tool is considered as one of most hopeful cutting tools by the international in present age. Now it is widely used in hundreds of factories
9、and more than twenty industries such as machinery, metallurgy, mine, automobile, tractor, bearing, bump, traffic, energy, precise instrument, aerospace and aeronautics, and bring about good economic benefit. For example the First Automobile Group, the Second Automobile Group and Shijiazhuang Bump Fa
10、ctory have all used ceramic tools to machine lower machinability materials. In the First Automobile Group, automobile sleeve cylinders containing boron and phosphorus are all machined with ceramic tools. However, about its property and making rational use can we get expected effects. 1. Choice of pr
11、oper names and types of ceramic tool The types of domestic cutting tool ceramic include: puteAl2O3 ceramic, Al2O3-carbide ceramic, Al2O3-TiC-metal ceramic etc. Al2O3 ceramic, which contains more than 99.9% of Al2O3, is normally white, so it is called White Ceramic. P1(Originally named AM) produced b
12、y Chengdu Tool Research Institute belongs to this type. Because of its good wear resistance, Al2O3 ceramic is available for machining of gray cast iron and plain carbon steel. However, the disadvantages of low strength, bad thermal vibration-proof and fracture toughness make it easy to fracture and
13、so it can not be used in roughing. Yet cold press process make it very cheap. Al2O3-carbide ceramic is obtained by adding carbide such as TiC, WC, Mo2C, TaC, NbC and Cr3C2 to Al2O3 and pressing. Among the carbides, what is used widest is TiC. On one hand, the property of this kind of ceramic is supe
14、rior to pure Al2O3 ceramic, on the other hand, its machinability varies along with the content of TiC. Al2O3 carbide ceramic is mainly used to machine of hardened-steel and all sorts of wear-resisting cast iron. In our country, M 16(originally named T8), AG2, SG3 and SG4 are all belong to it. Among
15、them, SG3 and SG4 contain WC. Al2O3-TiC metal ceramic, which is called ceramic-metal, is made by adding bonding metals (e. g. Ni, Mo) to Al2O3-TiC ceramic to improve its use range and bonding strength between Al2O3 and TiC, so it is useful for roughing. Our domestic ceramic-metal include AT6, LT35,
16、LT55, M4, M5, M6 etc. AT6 contains 50% Al2O3, 40%TiC, 5%Ni, 4.5%Mo and 0.5% Mg. Its bending strength is 0.88-0.93 GPa, and hardness is 93.5-94.5 HRA. When machining of high-strength quenching and tempering steel, the cutting speed can reach one to three times as fast general cemented tools, and its
17、duration is six to ten times as long as general cemented carbide tool. So this kind of ceramic is available for cutting gray cast iron and wear resisting cast iron at high speed. But what need to pay attention to is that when cutting harden steel, the effect using Al2O3-TiC metal ceramic is less tha
18、n that using Al2O3-TiC compound ceramic. Al2O3-SiC ceramic is a high property ceramic that is made by adding 20%-30% SiC crystal whisker(an element crystal containing some fiber structure whose diameter is less than 0.6m, its tensile strength is 7GPa and tensile elasticity coefficient is more than 7
19、00GPa). SiC crystal whisker, just like reinforcing bar in reinforced concrete, acts as obstacle that hinder and change the developing directions of crackle and greatly improve its value of fracture toughness Kc to 9MPa (while the Kc of Al2O3 compound ceramic is 4), so it is also called crystal whisk
20、er reinforce ceramic. This ceramic is available for interrupted cutting, roughing, milling, planning and drilling, it is also useful for cutting Nickel-based alloy, chilled iron and hardened-steel, but its price is several times as high as general Al2O3. Our domestic names of the ceramic are AW9 and
21、 SG5. Si3N4 based ceramic which is developed in 1980s, is a non-oxide ceramic. It is very hard (3000 to 5000 HV, is the material whose hardness is second only to diamond, CBN and BC ) and it heat resistance is so good that it can cut at temperature as high as 1300 -1400. Meanwhile, its strength (ben
22、ding strength is 1 -1.5 GPa) and toughness are better than Al2O3 based ceramic and its shock resistance is good, so it is especially available for big feed or interrupted cutting. Because of higher thermal conductivity, lower coefficient of thermal expansion and small elasticity coefficient of Si3N4, its thermal shock resistance is improved remarkably. This ceramic is available for machining of cast iron, high temperature alloy and