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Carbon black (with subtypes acetylene black, channel black, furnace black, lamp black and thermal black) is a material produced by the incomplete combustion of coal tar, vegetable matter, or petroleum products, including fuel oil, fluid catalytic cracking tar, and ethylene cracking in a limited supply of air.
Carbon is used in chemical reduction at high temperatures. Coke is used to reduce iron ore into iron (smelting). Case hardening of steel is achieved by heating finished steel components in carbon powder. Carbides of silicon, tungsten, boron, and titanium are among the hardest known materials, and are used as abrasives in cutting and grinding ...
The cold-work tool steels include the O series (oil-hardening), the A series (air-hardening), and the D series (high carbon-chromium). These are steels used to cut or form materials that are at low temperatures. This group possesses high hardenability and wear resistance, and average toughness and heat softening resistance.
Carbon tool steels: They lose their hardness at 200 °C; High speed steels: They lose their hardness at 600 °C, and are widely used in machining. Due to their ability to retain hardness at higher temperature, higher cutting speeds are possible. Cemented carbides: Harder than tool steels, but less tough. Can be used up to 900 °C.
D2 is a high-carbon, high-chromium die steel and is the highest carbon alloy tool and die steel typically used in knife making. [ citation needed ] With a chrome content of 12%, some call it a "semi-stainless", because of the lack of free Chromium in solution, even though it is defined by ASM and ANSI as stainless, which contains at least 11.5% ...
Oxy-propane torches are usually used for cutting up scrap to save money, as LPG is far cheaper joule for joule than acetylene, although propane does not produce acetylene's very neat cut profile. Propane also finds a place in production, for cutting very large sections. Oxy-acetylene can cut only low- to medium-carbon steels and wrought iron ...
The Troubled-Teen Industry Has Been A Disaster For Decades. It's Still Not Fixed.
The term "shungite" has evolved substantially since was originally used in 1879 to describe a black substance with more than 98% carbon found in veins near its type locality of Shunga. More recently the term has also been used to describe a wide variety of rocks containing similar carbon layers, leading to some confusion.