Copper-silicon alloys

Copper-silicon alloy (96 percent cooper, 3 percent silicon, 1 percent manganese), per ASTM B315, is furnished as seamless pipe and welding fittings in Schedule 10 and regular and extra-strong copper pipe thicknesses. It is easier to weld than copper. 

Copper-silicon alloys are not always suitable when exposed to certain media and liigh temperature, particularly above lOO C (212 F). Users should satisfy tliemselves that the alloy selected is satisfactory for the service for wliich it is to be used. 

Organosilanes, especially dimethyldichlorosilane (M2), are important chemicals used in the silicone industries. The direct reaction of silicon with an organic halide to produce the corresponding organosilanes as a gas-solid-solid catalytic reaction was first disclosed by Rochow [1]. In the reaction, a copper-containing precursor first reacts with silicon particles to form the catalytically active component, which is a copper-silicon alloy, the exact state of which is still under discussion. As the reaction proceeds. Si in the alloy is consumed, which is followed by the release of copper. This copper diffuses into the Si lattice to form new reaction centers until deactivation occurs. The main reaction of the direct process is ... 

Byproducts, such as methyltrichlorosilane (Mj), trimethylchlorosilane (M3), methyldichlorosilane (MH), and some residuals (R) having a boiling point above 70 C are also produced. One of the most efficient ways to prepare the active copper-silicon alloy is by the uniform mixing of CuCl and silicon particles. The following reaction takes place when the mixture is heated to the reaction temperature ... 

Nickel-chromium-molybdenum-copper-silicon alloy C, in galvanic series, 7 805t... 

B 96 Copper-Silicon Alloy Plate, Sheet, Strip, and Rolled Bar for General Purposes and... 

The main raw stock for the direct synthesis of methyl-, ethyl and phenylchlorosilanes is correspondingly methylchloride, ethylchloride and chlorobenzene, as well as copper-silicon alloy or mechanical mixture of silicon and copper powders (so-called contact mass). 

The main requirement to methylchloride, ethylchloride and chlorobenzene is the absence of impurities, by-products and especially moisture. With even the slightest amount of liquid entering the reaction zone, the products start to hydrolyse and condense, the activity of the contact mass or copper-silicon alloy decreases, and the process subsides. That is why the technology of direct synthesis usually provides for a device to dehydrate alkyl- and arylchlorides. For this purpose one can pass methyl- or ethylchloride through the tower sprayed with sulfuric acid, or use other dehydrating substances (burnt CaCF, AI203 and zeolites, e.g. burnt klinoptilo-lite). 

Grinding of copper-silicon alloy. Copper-silicon alloy before direct synthesis is subjected to grinding. The alloy enters the plant in the shape of fragments or plates weighing 60-80 kg. First, they are broken into pieces up to 75 mm in size, then crushed to 15-25 mm on a jaw crusher and dumped into the bottom of an elevator. The elevator feeds the alloy into a bin, and from the bin the alloy is sent through a branch pipe into ball grinders. The ground alloy is sent to the bin and from there to the synthesis reactor. 

To increase the diphenyldichlorosilane content in the condensate, it is advisable to conduct the direct synthesis of phenylchlorosilanes not with copper-silicon alloy but with a mechanical mixture of silicon and copper powders, promoted by zinc oxide. The introduction of zinc oxide seems to inhibit the undesirable reactions of diphenyl and benzene formation, creating favourable conditions to attach phenyl radicals to the silicon atom, i.t. to form diphenyldichlorosilane. 

Copper and Copper Alloys Seamless copper, bronze, brass, copper-nickel-alloy and copper-silicon-alloy pipe and tubing are produced by extrusion. Tubing is available in outside-diameter sizes from Vie to 16 in and in a range of wall thicknesses varying from 0.005 in for the smallest tubing to 0.75 in for the 16-in size. Tubing is usually specified by outside diameter and wall thickness. 

Hydrolysis of the alkyl and aryl substituted silicon halides produces silicones (Kipping, 1937). The halogen derivatives themselves are made by passing an alkyl or aryl halide over a copper-silicon alloy at about 300°. Hurd and Rochow (1945) found evidence for the mechanism ... 

Although stainless steels were discovered at the turn of the century and copper silicon alloys started to emerge at about the same time, the real explosion of materials research and development began at around the beginning of World War II. Polymer science and technology were no exception. Nylon was already developed at the DuPont Company. Alloy 20 was developed by DuPont in the late thirties. At about the same time, polytetrafluoroethylene (PTFE) (Teflon ) was discovered which led to further development of fluoropol5miers and ushered in an era of high-performance polymer materials for corrosion control. 

Item to. Chart for determining shell thickness of cylindrical and spherical vessels under external pressure when constructed of copper-silicon alloys A ond C. From the 1956 ASME Unflred Pressure Vessel Code with permission of die Am. Soc. Mech. Engrs. ... 

Metals used for liquid hydrogen equipment must have satisfactory properties at very low operating temperatures. Ordinary carbon steels lose their ductility at liquid hydrogen temperatures and are considered too brittle for this service. Suitable materials include austenitic chromium-nickel steels (stainless steels), copper, copper silicon alloys, aluminum. Monel, and some brasses and bronzes. 

It is possible that the improvements described above are due to pre-formation of silicon copper alloys, as claimed by Elattar. Improved activity of MCS contact mass was obtained by forming a contact mass of particulate Si and Cu (16.9% metallic Cu, 45.5% CU2O, 36.9% CuO) by heating the mass in the presence of MeCl gas at 305 °C for a time sufficient to form active spots of Cu-Si alloy on the surface. The nature of these copper-silicon alloys may include those described by some former E. German workers who showed the importance of forming CusSi and CuSia among others. ... 

C6xxxx Copper-aluminum alloys, copper-silicon alloys (silicon bronzes), and other copper-zinc alloys... 

Part 5. Copper-silicon alloys (silicon bronzes and silicon brasses) ... 

G. P. Khilya and Yu. I. Vashchenko, 1973, Free surface energy and density of liquid copper-silicon alloys , Dopov Akad Nauk Ukr RSR Ser. B 35, 69-72. 

A recent extensive study of the process (R. J. H. Voorhoeve, 1964) has shown that neither adding sources of methyl radicals nor adding radical scavengers has significant effect. The reactive solid phase is a copper-silicon alloy (about Cu3Si in composition) in which the copper is positively... 

Monnier and his co-workers were able to obtain 99.9 to 99.99% pure silicon from SiOj - cryolite solutions in a two step process. The first step was the deposition of silicon to form a molten copper-silicon alloy at the... 

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