Nickel-chrome

Aluminum 0.35 A.l.S.1. 300 Series S/Steels 1.02 Nickel-Chrome-lron 1.07... 

The desire to replace cadmium is generally attributed to its toxicity, both in terms of process pollution and product corrosion, and several alternatives are feasible thicker zinc, tin-zinc alloy or tin-nickel alloy depending upon the precise application " . The demise of decorative nickel-chrome systems in the automotive industries of the world is partly due to cost and partly to market image, and not to technical performance where major improvements took place in the period 1960-1975 through the establishment of duplex nickel under-layers and micro discontinuous chromium top-layers. In the 1980s the trend has been towards black finishes produced generally by powder-applied epoxy polymers. 

A more recent use of nickel is in the manufacture of the rechargeable nickel-chrome electric cell. One of the electrodes in this type of cell (battery) is nickel (11) oxide (Ni + O — NiO). (Note When two or more cells are combined in an electrical circuit, they form a battery, but when just one is referred to, it is called a cell.) Although the electrical output of a Ni-Chrome cell is only 1.4 volts (as compared to 1.5 volts dry cells), Ni-Chrome has many uses in handheld instruments such as calculators, computers, electronic toys, and other portable electronic devices. 

The apparatus is shown in Fig. 4.1. The body of the extraction vessel is made from Pyrex. Separation is effected by absorption of a batch containing both phases into a porous 2 cm diameter nickel-chrome alloy disc (A), the upper surface of which is domed. The disc is mounted on the end of a stainless-steel shaft (B) turned by a geared high-torque electric motor. The disc-shaft-motor assembly can he transported along its axis of rotation to any of three stations. The assembly is shown at its bottom station, with the porous disc within the inner vessel (C), around which is a collar (D) forming the first annular pocket (E). The collar itself forms the inner wall of the second annular pocket (F), the outer wall of which extends upwards to support a Perspex Hd (G) on which the rotor (H) is situated. The inner vessel and both annular pockets are fitted with drain valves. A stiff piece of platinum wire is passed through the Hd into the glassware as far as the level of the first annular pocket. 

The nickel-chrome alloy is available from the Dunlop Aviation Group and has the trade name of Retimet . Retimet is suitable, although its affinity for the organic phase is greater than for the aqueous phase. In order to produce approximately equal affinity for each phase the discs were gold plated for 10 min using a current of 300 mA. It is preferable that the alloy is shaped so that the pore structure is maintained on the surface after machining. Spark erosion is used to shape the material. 

A steel ball, diam and weighing 8 33 S, was dropped from a height 25 on a 0.08" layer of LA spread on 1" thick SAE 3260, nickel-chrome, hardened steel block which rested on a 1%" thick by 12" diam cast iron base. Ten consecutive drops should produce no detonations in a properly manufd LA, but when the ball was dropped from the height of 45", it should deton in all trials. Care was taken not to drop the ball on the same spot twice, as a pellet made by the first drop would usually fire if hit a second time. If... 

S ickel—Magnesium, in eomhinalion with carbon, forms an age-hardenable alloy, The main use of magnesium is to deoxidize and desulfurize the melts, including pure nickel, nickel-chrome, and nickel-copper alloys. 

Prepare a detection window by using a heating device made of a coiled nickel-chrome wire. 

Nitric acid pickling is generally restricted to low-carbon stainless steels of the 200 (nickel-chrome-manganese), 300 (nickel-chrome) and 400 (chrome) series. 

Use only high-grade nickel chrome wire employed by model builders to home-turn smalt springs. Generally, diameters of between. 015- and. 02G-inch are best, but if one has a less sensitive primer, more powerful batteries must be used with heavier wire. Anything over. 025-inch diameter will probably blow fuzes in a residential electrical system. This is definitely the upper size limit for bridge wires. 

Cut a piece of nickel chrome spring wire about 6 inches long. Bend it into a hairpin, using pliers if necessary Using a screwdriver, small punch, dull cold chisel, or, as neces-... 

Builders who do not have access to aluminum tube or nickel chrome wire can use a standard PR-6 flashlight bulb. Carefully crack the glass away leaving the filament perfectly intact. Solder a wire lead to the back end and side of the bulb. Carefully place the intact filament into.the priming mixture. It Isn t as good as nickel chrome wire, but it will work. 

In recent years, a number of especially resistant iron alloys have appeared on the market and have been rapidly adopted. They are, essentially, nickel-chrome-iron alloys, usually containing very little carbon. These alloys are very resistant to acids and alkalis and are used chiefly where high resistance to chemicals is the deciding factor. The different VA-steels, and the English S-80, are examples of these alloys which vary in composition depending on the particular application. These alloys withstand concentrated nitric acid, and other acids, except hydrochloric, scarcely attack them at all. They are especially important in modem high pressure syntheses. Potassium hydroxide scarcely attacks these alloys even in fusion mixtures, and they are quite satisfactory, therefore, for indanthrene fusions. (Nickel is also suitable in this particular case.)... 

A nickel-chrome spinel, NiO.CrjOg, has been made artificially in small green crystals. The green colour of emerald, serpentine, possibly sapphire, and other minerals is due to the presence of compounds of chromium, which also occur in rubies, corundums, and spinels. It has been shown that the peculiar spectra of ruby and diamond are due to chromium oxide which has been compelled to vibrate in an abnormal manner, leading to the production of narrow absorption bands. Traces of chromium have been detected in the soot produced by the combustion of coal obtained from deposits at Li ge. Compounds of chromium are not known to play any part in the economy of plants or animals. 

Weights are based on low-carbon steel with a density of 0.2836 Ib/cu. in. For other metals multiply by the following factors aluminum, 0.35 titanium, 0.58 A.I.S.I. 400 Series S/steels, 0.99 A.I.S.I. 300 Series S/steels, 1.02 aluminum bronze, 1.04 aluminum brass, 1.06 nickel-chrome-iron, 1.07 Admiralty, 1.09 nickel, 1.13 nickel-... 

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