Steel copper-bearing

An interesting development in weldable corrosion-resistant steels is the copper-bearing or weathering steels (Section 3.2) which exhibit enhanced corrosion resistance in industrial atmospheres in the unpainted condition. For optimum corrosion resistance after welding, the filler employed should be suitably alloyed to give a deposit of composition similar to that of the steel plate... 

Fig. 2.16. The PlEgli valve. A stainless steel ball bearing, B orifice to be closed by A, C copper bellows, D cover-plate, E sharp annular ridge, F channel full of solder, G, H sockets for Housekeeper seals, J screws securing D to body of valve.

This acid is very corrosive towards most of the common metals and alloys. The corrosivity is increased where aeration or contamination by oxidising agents is present. Copper is particularly prone to this problem. Also many failures occur due to the presence of minor impurities such as ferric chloride. Rubber-lined steel is widely used for pipelines and large or small vessels. The rubber compound should be free from copper bearing antioxidants or accelerators. 

Derivation Electrolysis of molten anhydrous hydrofluoric acid-potassium fluoride melts with special copper-bearing carbon anodes, steel cathodes and containers, and Monel screens. 

Copper Cu 0.10, C ca. 0.2 Improved corrosion resistance Copper-bearing steels, bridges, exterior steelwork... 

Corrosion-product films formed in the atmosphere tend to be protective that is, the corrosion rate decreases with time (Fig. 9.1) [3]. This is true to a lesser extent of pure iron, for which the rate is relatively high, compared to the copper-bearing or low-alloy steels, which are more resistant. Rust films on the latter steels tend... 

Hsi] Hsiao, C.N., Yang, J.R., Age Hardening in Martensitic/Bainitic Matriees in a Copper-Bearing Steel , Mater. Trans., JIM, 41(10), 1312—1321 (2000) (Experimental, Morphology, Meehan. Prop., 25)... 

Kelley, V. 1. (1975). Atmospheric Corrosion Investigation of Aluminium-Coated, Zinc-Coated and Copper-Bearing Steel Wire and Wire Products. A Twelve-Year Report. ASTM STP 585, ASTM, Philadelphia, 89 pp. 

Small amounts of alloying elements in steel can have a significant beneficial effect on corrosion in the atmosphere. Copper-bearing steels (0.2 % copper, minimum) have long been used for this purpose. In the HSLA weathering steels, small additions of elements such as chromium, silicon, copper, nickel, and phosphorus are used to achieve even greater resistance to atmospheric corrosion. 

Phosphorus also helps to improve the corrosion resistance of weathering steels. By increasing the phosphorous content from less than 0.01% to 0.1%, a 20-30% improvement in the corrosion resistance of copper-bearing steels is realized. Phosphorus may form layers of insoluble phosphates in the rust, acting as transportation barriers in the same manner as the basic sulfates previously mentioned. A comparison of the corrosion rates of carbon steel, a copper-phosphorous low-alloy steel, and a chromium-vanadium-copper low-alloy steel are shown in Table 4.2. 

Another type of design is the nozzle with copper/cobalt/beryllium alloy casing located inside a steel body bearing an external load (Figures 4.17b and 4.17c). In a nozzle used with reinforced plastics and plastics with an injection temperature of over 280 °C, the casing is made of molybdenum. The nozzle may have a full- or partial-body 4.17(b). 

The 300 series stainless steels have given excellent service, as have nickel, monel, and K-monel. Copper and copper bearing alloys have been used to an... 

The columns shall be constructed of materials that are inert and nonadsorptive with respect to the components in the sample. The preferred material of construction is stainless steel. Copper and copper-bearing alloys are unacceptable. 

The coating thickness may range from 0.0025 to 0.05 mm, depending on the type of protection required. Pure tin coatings are used on food-processing equipment, milk cans, kitchen implements, electronic and electrical components, fasteners, steel and copper wire, pins, automotive bearings, and pistons. 

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