Borided tools

Via holes larger than > 0.5 mm (0.020 in.) are usually very easy to form, since materials such as tungsten carbide can be used as punching tools. For smaller holes, in the range of 0.25 mm or less, tungsten carbide may be too brittle, and other materials such as borided tool steel should be used. There are several companies that boride the tool steel punches that have been machined to size. 12 This process yields a punch with the surface hardness of a carbide but with some flexibility. 

The synthetic method used in preparing a particular boride phase depends primarily on its intended use. Whereas for basic research borides of high purity are desirable, for industrial applications, e.g., in coatings, tools and crucibles, as a refining agent in metallurgy or in control rods in nuclear energy plants, pure borides are unnecessary. 

Molybdenum boride (Mo B) is used to braze (weld) special metals and for noncorrosive electrical connectors and switches. It is also used to manufacture high-speed cutting tools and noncorrosive, abrasion-resistant parts for machinery. 

Numerous ceramics are deposited via chemical vapor deposition. Oxide, carbide, nitride, and boride films can all be produced from gas phase precursors. This section gives details on the production-scale reactions for materials that are widely produced. In addition, a survey of the latest research including novel precursors and chemical reactions is provided. The discussion begins with the mature technologies of silicon dioxide, aluminum oxide, and silicon nitride CVD. Then the focus turns to the deposition of thin films having characteristics that are attractive for future applications in microelectronics, micromachinery, and hard coatings for tools and parts. These materials include aluminum nitride, boron nitride, titanium nitride, titanium dioxide, silicon carbide, and mixed-metal oxides such as those of the perovskite structure and those used as high To superconductors. 

EINECS 234-963-5 Zirconium boride Zirconium boride (ZrB2) Zirconium diboride Zirconium diboride (ZrB2). Refractory for aircraft and rocket applications, thermocouple protection tubes, high-temp, electrical conductor, cutting-tool component, coating tantalum, cathode in high-temp, electrochemical systems oxidation-resistant composites. Atomergic Chemetals Cerac Noah Cham. 

Finally, two other characteristics of hard materials are important their density and their chemical stability. The importance of these properties depends on the application. Oxides are chemically more stable than nitrides, which are in turn more stable than borides or carbides. The susceptibility to oxidation of boron carbide prevents its application at high temperatures, but for ballistic protection, where hardness, rigidity and low density take precedence, boron carbide is unparalleled. Tungsten carbide, on the other hand, is the material of first choice for cutting tools, because of its high hardness and stiffness, and high-temperature oxidation resistance, but is far too dense for application in which weight or inertial forces are important. Its use for ballistic protection is therefore out of the question. 

Hard materials available for the production of bulk components fall into two major groups hard metals , used primarily in the manufacture of cutting tools and related applications, and structural ceramics, primarily the oxides, carbides, borides, or nitrides of the low atomic number cations. Relatively few materials are of engineering importance, and we will list these, explaining briefly why similar compositions are less useful. 

In February, 1980, Sumitomo from Japan filed the patent Sintered compact for a machining tool and a method of producing the compact [161]. This patent basically covers any compact with 10-80 vol% cBN and a balance of binder material that can comprise any carbides, nitrides, borides, or silicides of metals of groups IVa, Va, or Via. Specifically mentioned are titanium, zirconium, hafnium, vanadium, niobium. 

Most of the developments in cemented borides aim at the high wear resistance due to the superior hardness compared to carbide-based hard metals. One of the most important applications are, therefore, the cutting tools where cemented boride have to compete with tungsten carbide, titanium carbonitride, and ceramic materials as well. 

Hard materials are used as thin hard coatings of some microns thickness for wear protection of tools and machine parts because of their high abrasive wear resistance. For the selection of the coating material the physical, mechanical, and technological properites of these coatings, required by the application, are decisive. The following data collection presents fundamental and available material properties for approximately 130 hard materials as a result of a literature search on carbides, nitrides, borides, silicides, and oxides. 

Ammonium xylenesulfonate Caprylic/capric acid Chlorodiphenyl (54% Cl) 2-Ethylhexyl oleate Pentaerythrityl tetrabehenate Soy acid Tall oil y-Valerolactone cutting oils, metals Isopropanolamine cutting tools/dies Tantalum carbide cutting-tool component refractory Zirconium boride cyanamide mfg. 

Potentially useful single crystal HP-LCVD fibers include hafnium boride and tantalum carbide and have projected service temperatures ranging from 2170 to 2715 C. Presently envisioned applications include the potential use of these fibers as consumable sensors to monitor rocket exhaust temperatures. Other HP-LCVD sensor fibers, including Si, Ge and ZnSe, (Figure 15), promise to offer high value in premium automotive and medical sensor systems. Single crystal HP-LCVD germanium [20] and silicon carbide [21] fibers can now also become available for exploration. In summary, the HP-LCVD process is an ideally suited tool for the rapid fabrication and evaluation, without extensive process research, of test samples of potentially new fiber candidates for structural and sensor uses. 

Cermet sor- met] [ceramic + metal] (1948) n. (1) Composite materials consisting of two components, one being either an oxide, carbide, boride or similar inorganic compound and the other a metallic binder. (2) Any refractory composition made by bonding grains of ceramics, metal carbides, nitrides, etc, with a metal. Co-deposition of cermets with nickel in the electroless-nickel process provides excellent wear resistance and chemical resistance to molds, dies, extruder screws and other tooling components used in the plastics industry. 

---