| Make sure it is night when you do this spell. Also, light one orange and one pink candle. Close your eyes. (You Must Have complete focus and be concentrating on the spell, ONLY.) Fill your mind with the color your eyes are. Picture that for abo... Read more of Spell to change eye color at White Magic.ca |  InformationalPrivacy |
Steel MakingMaking Steel BallsSteel balls are made from rods or coils according to size, st... Heat Treatment Of Steel Heat treatment consists in heating and cooling metal at defin... Liberty Motor Connecting Rods The requirements for materials for the Liberty motor connecti... Optical System And Electrical Circuit Of The Leeds & Northrup Optical Pyrometer For extremely high temperature, the optical pyrometer is lar... Correction By Zero Adjustment Many pyrometers are supplied with a zero adjuster, by means ... Oil-hardening Steel Heat slowly and uniformly to 1,450 deg.F. and forge thorough... Judging The Heat Of Steel While the use of a pyrometer is of course the only way to hav... Gas Consumption For Carburizing Although the advantages offered by the gas-fired furnace for ... Annealing To Relieve Internal Stresses Work quenched from a high temperature and not afterward tempe... Non-shrinking Oil-hardening Steels Certain steels have a very low rate of expansion and contract... High-chromium Or Rust-proof Steel High-chromium, or what is called stainless steel containing f... Lathe And Planer Tools TO FORGE.--Gently warm the steel to remove any chill is parti... Heat Treatment Of Milling Cutters Drills Reamers Etc THE FIRE.--Gas and electric furnaces designed for high heats ... Preventing Carburizing By Copper-plating Copper-plating has been found effective and must have a thick... The Packing Department In Fig. 56 is shown the packing pots where the work is packe... The Influence Of Size The size of the piece influences the physical properties obta... Corrosion This steel like any other steel when distorted by cold worki... Restoring Overheated Steel The effect of heat treatment on overheated steel is shown gra... Carburizing By Gas The process of carburizing by gas, briefly mentioned on page ... Preparing Parts For Local Case-hardening At the works of the Dayton Engineering Laboratories Company, ... |
Introduction Of CarbonCategory: CASE-HARDENING OR SURFACE-CARBURIZING The matter to which these notes are primarily directed is the introduction of carbon into the case of the article to be hardened. In the first place the chances of success are increased by selecting as few brands of steel as practicable to cover the requirements of each component of the mechanism. The hardener is then able to become accustomed to the characteristics of that particular material, and after determining the most suitable treatment for it no further experimenting beyond the usual check-test pieces is necessary. Although a certain make of material may vary in composition from time to time the products of a manufacturer of good steel can be generally relied upon, and it is better to deal directly with him than with others. In most cases the case-hardening steels can be chosen from the following: (1) Case-hardening mild steel of 0.20 per cent carbon; (2) case-hardening 3-1/2 per cent nickel steel; (3) case-hardening nickel-chromium steel; (4) case-hardening chromium vanadium. After having chosen a suitable steel it is best to have the sample analyzed by reliable chemists and also to have test pieces machined and pulled. To prepare samples for analysis place a sheet of paper on the table of a drilling machine, and with a 3/8-in. diameter drill, machine a few holes about 3/8 in. deep in various parts of the sample bar, collecting about 3 oz. of fine drillings free from dust. This can be placed in a bottle and dispatched to the laboratory with instructions to search for carbon, silicon, manganese, sulphur, phosphorus and alloys. The results of the different tests should be carefully tabulated, and as there would most probably be some variation an average should be made as a fair basis of each element present, and the following tables may be used with confidence when deciding if the material is reliable enough to be used. TABLE 16.--CASE-HARDENING MILD STEEL OF 0.20 PER CENT CARBON Carbon 0.15 to 0.25 per cent Silicon Not over 0.20 per cent Manganese 0.30 to 0.60 per cent Sulphur Not over 0.04 per cent Phosphorus Not over 0.04 per cent A tension test should register at least 60,000 lb. per square inch. TABLE 17.--CASE-HARDENING 3-1/2 PER CENT NICKEL STEEL Carbon 0.12 to 0.20 per cent Manganese 0.65 per cent Sulphur Not over 0.045 per cent Phosphorus Not over 0.04 per cent Nickel 3.25 to 3.75 per cent TABLE 18.--CASE-HARDENING NICKEL CHROMIUM STEEL Carbon 0.15 to 0.25 per cent Manganese 0.50 to 0.80 per cent Sulphur Not over 0.045 per cent Phosphorus Not over 0.04 per cent Nickel 1 to 1.5 per cent Chromium 0.45 to 0.75 per cent TABLE 19.--CASE-HARDENING CHROMIUM VANADIUM STEEL Carbon Not over 0.25 per cent Manganese 0.50 to 0.85 per cent Sulphur Not over 0.04 per cent Phosphorus Not over 0.04 per cent Chromium 0.80 to 1.10 per cent Vanadium Not less than 0.15 per cent Having determined what is required we now proceed to inquire into the question of carburizing, which is of vital importance. Next: Using Illuminating Gas Previous: The Penetration Of Carbon
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