Blue brittleness

Grayish-black to steel-blue, brittle, or fibrous pieces producing a black, or grayish-black, streak. The preparation contains about 90 per cent of Mn02. 

Cupric hydroxide, Cu(OH)2.—The hydroxide has been prepared in crystalline form by the action of a solution of caustic alkali on a basic cupric nitrate 2 and a basic cupric sulphate,3 and also by other methods.4 A hydrogel of varying composition is precipitated by addition of alkali to solutions of cupric salts.5 Unlike the colloidal form, the blue crystalline variety is stable at 100° C. A solid, colloidal variety has been obtained 6 as blackish-blue, brittle lamellae which dissolve in water to form the original solution. An amorphous modification is precipitated from ammoniaeal copper solutions by the action of alkali-metal hydroxides.7... 

Various pressure vessels having shell thicknesses of 3 to 6 inches have failed in a blue-brittle manner at temperatures where the material exhibited 50 or more ft.-lb. Charpy V-notch impact energy. 

Gray-blue, brittle homogeneous contains 33 and 35 atom% Te. M.p. about 900°C. d 7.338. Crystal structure hexagonal (special type), defect lattice at Cu <3 Te. 

Unlike the older, simple iron manufacturing processes, pig iron takes up the total phosphorus content from the ore. Iron made from a high-phosphorus pig iron will have a high content of phosphorus and suffer from blue brittleness. Thus, only iron ores with low phosphorus contents could be used in the blast furnace process for production of a high-quality iron. In the new situation in Europe the production units had to be located in regions with a large supply of ore with low phosphorus - and high iron - contents. Some examples are shown in Table 8.1. 

Severe loss of ductility of a metal (or alloy) loss of load carrying capacity of a metal or alloy the severe loss of ductility or toughness or both, of a material, usually a metal or alloy. Many forms of embrittlement can lead to brittle fracture and many can occur during thermal treatment or elevated-temperature service (thermally induced embrittlement). Some of these forms of embrittlement, which affect steels, include blue brittleness, 885 °F (475 °C) embrittlement, quench-age embrittlement, sigma-phase embrittlement, strain-age embrittlement, temper embrittlement, tempered martensite embrittlement, and thermal embrittlement. In addition, steels and other metals and alloys can be embrittled by environmental conditions (environmentally assisted embrittlement). Forms of environmental embrittlement include acid embrittlement, caustic embrittlement, corrosion embrittlement, creep-rupture embrittlement, hydrogen embrittlement, bquid metal embrittlement, neutron embrittlement, solder embrittlement, sobd metal embrittlement, and stress-corrosion cracking. 

Of the fibrous fillers which greatly reduce the brittleness, blue asbestos fibre is normally used for battery boxes, the principal outlet. Other materials that may be used include cotton fibres, ground wood, slag wool and ground cork. 

Cadmium is a soft, blue-white metal that is malleable and ductile although it becomes brittle at about 80°C. It is also found as a grayish-white powder. It is considered rare and is seldom found by itself as an ore. Its melting point at 320.9°C is considered low. Its boiling point is 765°C, and its density is 8.65 g/cm. Certain alloys of cadmium have extremely low melting points at about 70°C. 

The pure form of tellurium burns with a blue flame and forms tellurium dioxide (TeO ). It is brittle and is a poor conductor of electricity. It reacts with the halogens of group 17, but not with many metals. When it reacts with gold, it forms gold telluride. Tellurium is insoluble in water but readily reacts with nitric acid to produce tellurous acid. If inhaled, it produces a garlic-like odor on one s breath. 

The incandescent mantle was however not accepted by consumers because it was too brittle and produced a "cold" blue-green light. 

Carbonate of lead—sparry lead ore—is remarkable for its transparency and lustre when in its purity. Several varieties of this ore are known. It is fouud in the form of ncicular crystals, in compact masses, and often presenting a fibrous, lamellar, and earthy appearance. They all, with the exception of the earthy species, possess a peculiar lustre, like that of whita lead. Earthy carbonate of lead presente several shades of color— brown, green, or blue—dependent upon the nature of the metal associated with it. The mineral is veiy brittle, and its fracture has a waved eonclioidal ap-pearanoe. Its specific gravity varies from 6 to 6 7. 

ANATASE. The mineral anatase, TiC>2 crystallizing in the tetragonal system is a relatively uncommon mineral. It occurs as a tri-morphous form of Ti02 with rutile mid brookite. Rutile and anatase have tetragonal crystallization brookite, orthorhombic. Hardness, 5.5-6 sp. gr. 3.82-3.97 brittle with sub-conchoidal fracture color, shades of brown, into deep blue to black also colorless, grayish, and greenish also transparent to opaque with adamantine luster. 

AZURITE. This mineral is a basic carbonate of copper, crystallizing in the monoclinic system, with the formula Cu2.(C03)2(0H)2, so called from its beautiful azure-blue color. It is a brittle mineral with a conchoidal fracture hardness. 3.5-4 sp gr, 3.773 luster, vitreous, color and streak, blue transparent to translucent Azurite, like malachite, is a secondary mineral, but for less common than malachite. It is formed by the action of carbonated waters on compounds of copper or solutions of copper compounds. 

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