Alloying agents

Beryllium is used as an alloying agent in producing beryllium copper, which is extensively used for springs, electrical contacts, spot-welding electrodes, and non-sparking tools. It is applied as a structural material for high-speed aircraft, missiles, spacecraft, and communication satellites. Other uses include windshield frame, brake discs, support beams, and other structural components of the space shuttle. 

Titanium is important as an alloying agent with aluminum, molybdenum, manganese, iron, and other metals. Alloys of titanium are principally used for aircraft and missiles where lightweight strength and ability to withstand extremes of temperature are important. 

The characteristics of a pressed compact are influenced by the characteristics of the powder rate and manner of pressure appHcation, maximum pressure appHed and for what period of time, shape of die cavity, temperature during compaction, additives such as lubricants and alloy agents, and die material and surface condition. The effect of various compaction variables on the pressed compact are shown in Figure 6. 

Mixed zircon, coke, iron oxide, and lime reduced together produce zirconium ferrosiUcon [71503-20-3] 15 wt % Zr, which is an alloy agent. Fused zirconia [1314-23-4] has been made from zircon but baddeleyite is now the preferred feed for the production of fused zirconia and fused alumina—zirconia by electric-arc-fumace processing. 

Low-Alloy Steels Alloy steels contain one or more alloying agents to improve mechanical and corrosion-resistant properties over those of carbon steel. 

A typical low-alloy grade [American Iron and Steel Institute (AISI) 4340] contains 0.40 percent C, 0.70 percent Mn, 1.85 percent Ni, 0.80 percent Cr, and 0.25 percent Mo. Many other alloying agents are used to produce a large number of standard AISI and proprietary grades. 

Aluminum also improves the resistance of iron to oxidation as well as sulfidation. But use as an alloying agent is limited because the amount required interferes with the worl bility and high-temperature... 

Table 14.14 Effect of a titanate alloying agent (Kenrich Lica-12) on a 80/20 PET/PC blend (data obtained from Kenrich Petrochemicals Ltd)...

Calcium oxide was used in ancient times to make mortar for building with stone. Both the metal and calcium compounds have many industrial as well as biological uses. Metallic calcium is used as an alloy agent for copper and aluminum. It is also used to purify lead and is a reducing agent for beryllium. 

Gadoliniums main use is based on its ability to absorb neutrons, thus making it ideal as a neutron-shielding and neutron-absorbing metal. It is also used as an alloying agent for steel and other metals to make the metals more workable and to be able to withstand low temperatures. 

Because beryllium is primarily used as a powder metallurgy product or as an alloying agent, casting technology in the conventional metallurgical sense is not commonly utilized with the pure metal. 

The primary industrial use of calcium metal is as an alloying agent to harden aluminum. Calcium compounds such as lime and gypsum are used for many purposes throughout the chemical and construction industries. Portland cement, for example, contains approximately 70% CaO. In addition, calcium is the primary constituent of teeth and bones. 

Because hafnium has a high absorption cross-section for thermal neutrons (almost 600 times that of zirconium), has excellent mechanical properties, and is extremely corrosion resistant, it is used to make the control rods of nuclear reactors. It is also applied in vacuum lines as a getter —a material that combines with and removes trace gases from vacuum tubes. Hafnium has been used as an alloying agent for iron, titanium, niobium, and other metals. Finely divided hafnium is pyrophoric and can ignite spontaneously in air. 

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