Zirconium-lead alloys

Zirconium-Lead Alloys. These alloys, contg from 10 to 70% Zr, are claimed to pulverize and ignite on impact... 

Zirconium/lead alloys in a wide range of proportions spark or catch fire on impact and have been proposed for use as impact igniters for incendiary bullets, or as tracers that mark the impact of a projectile by the light effect. Similar alloys mixed with organic fuels are claimed in a U. S. patent as self-igniting incendiaries. ... 

Materials such as metals, alloys, steels and plastics form the theme of the fourth chapter. The behavior and use of cast irons, low alloy carbon steels and their application in atmospheric corrosion, fresh waters, seawater and soils are presented. This is followed by a discussion of stainless steels, martensitic steels and duplex steels and their behavior in various media. Aluminum and its alloys and their corrosion behavior in acids, fresh water, seawater, outdoor atmospheres and soils, copper and its alloys and their corrosion resistance in various media, nickel and its alloys and their corrosion behavior in various industrial environments, titanium and its alloys and their performance in various chemical environments, cobalt alloys and their applications, corrosion behavior of lead and its alloys, magnesium and its alloys together with their corrosion behavior, zinc and its alloys, along with their corrosion behavior, zirconium, its alloys and their corrosion behavior, tin and tin plate with their applications in atmospheric corrosion are discussed. The final part of the chapter concerns refractories and ceramics and polymeric materials and their application in various corrosive media. 

The zircaloy series of alloys was developed by the U.S. Navy Nuclear Propulsion Program for service in the core of water-cooled nuclear reactors [R3]. Compared with pure zirconium, these alloys have greater strength and better resistance to corrosion by water or steam. Zircaloy-4 was developed later than zircaloy-2 and became the preferred material, because the nickel in zircaloy-2 promoted the absorption of hydrogen, leading to reduction in ductility. 

The most stable solid oxide phase corresponds to the stoichiometry Zr02. Oxygen deficient Zr02 x or zirconium-oxygen alloys exist only under extremely reducing conditions. Reduction of zirconium dioxide by carbon at 1610 to 1680 K leads to the formation of ZrO 95 [78KUT/ZHE]. Amorphous hydrous oxides and basic salts are known to precipitate from aqueous solution. 

Zirconium-based alloys have received special attention, leading to the discovery, by Johnson group, " of several stable glasses and among them the complex composition (ZrsTOo,55 (Cu5Ni4)o,225660,225- This material called Vitreloy 1 (VI) is a commercial product used, for instance, for the fabrication of golf clubs. 

In the nuclear industry, stainless steel was used to clad the uranium dioxide fuel for the first-generation reactors. But by 1965, the force of neutron economy had made zirconium alloys the predominant cladding material for water-cooled reactors. There was a widespread effort to develop strong, corrosion-resistant zirconium alloys. Noticeably, the Ozhennite alloys were developed in the Soviet Union for use in pressurized water and stream. These alloys contain tin, iron, nickel, and niobium, with a total alloy content of 0.5-1.5%. The Zr-1% Nb alloy also is used in the Soviet Union for pressurized water and steam service. Researchers at Atomic Energy of Canada Ltd. took a lead from the Russians zirconium-niobium alloys and developed the Zr-2.5% Nb alloy. This alloy is strong and heat-treatable. It is used either in a cold-worked condition or a quenched-and-aged condition. 

The traditional additions are chromium, manganese (these two elements improve weldability), nickel (improves resistance at high temperatures), titanium (refining the as-cast structure), beryllium, zirconium, lead (free machining alloys), etc. An alloy can contain more than one additive, and their concentrations may exceed 1 % in certain cases. All the alloying elements can also be additives in another series of alloys. 

There is a noticeable difference between the appearance of the aluminium-containing magnesium-rich alloys on the one hand and the zinc/zirconium-containing magnesium alloys on the other. In the former the microscopic pits in the surface which has been exposed to the weather tend to be narrow and relatively deep, while in the latter they are wider and tend to overlap, leading to a slightly wavy appearance. 

Individually indexed alloys or intermetallic compounds are Aluminium amalgam, 0051 Aluminium-copper-zinc alloy, 0050 Aluminium-lanthanum-nickel alloy, 0080 Aluminium-lithium alloy, 0052 Aluminium-magnesium alloy, 0053 Aluminium-nickel alloys, 0055 Aluminium-titanium alloys, 0056 Copper-zinc alloys, 4268 Ferromanganese, 4389 Ferrotitanium, 4391 Lanthanum-nickel alloy, 4678 Lead-tin alloys, 4883 Lead-zirconium alloys, 4884 Lithium-magnesium alloy, 4681 Lithium-tin alloys, 4682 Plutonium bismuthide, 0231 Potassium antimonide, 4673 Potassium-sodium alloy, 4646 Silicon-zirconium alloys, 4910... 

Alloys of reactive metals are often more pyrophoric than the parent metals. Examples are alloys of titanium with zirconium thorium with copper, silver or gold uranium with tin, lead or gold magnesium with aluminium hafnium with iron [1], Cerium amalgams and thorium-silver alloys are spontaneously flammable when dry [2], Individually indexed alloys are ... 

As the solubility is exceeded in the zirconium, precipitation of zirconium hydride commences and ultimately the ductility of the alloy can be reduced leading to the possibility of cracks. Thus an additional requirement in fuel development was a thorough understanding of the hydriding mechanism, sources of hydrogen, rate controlling steps, protective methods, specifications of materials and processes, and quality assurance to achieve the required performance. ( 3)... 

Lead, tantalum, zirconium, and many specialty alloys are not attacked by concentrated acid even at moderate temperatures. Containers made of such materials can be used for handling, storage, and carrying out reactions. 

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