Copper tensile strength

Tables 1 and 2, respectively, Hst the properties of manganese and its aHotropic forms. The a- and P-forms are brittle. The ductile y-form is unstable and quickly reverses to the a-form unless it is kept at low temperature. This form when quenched shows tensile strength 500 MPa (72,500 psi), yield strength 250 MPa (34,800 psi), elongation 40%, hardness 35 Rockwell C (see Hardness). The y-phase may be stabilized usiag small amounts of copper and nickel. Additional compilations of properties and phase diagrams are given ia References 1 and 2.

Copper and tin phosphides are used as deoxidants in the production of the respective metals, to increase the tensile strength and corrosion resistance in phosphor bronze [12767-50-9] and as components of brazing solders (see Solders and brazing alloys). Phosphor bronze is an alloy of copper and 1.25—11 wt % tin. As tin may be completely oxidized in a copper alloy in the form of stannic oxide, 0.03—0.35 wt % phosphoms is added to deoxidize the alloy. Phosphor copper [12643-19-5] is prepared by the addition of phosphoms to molten copper. Phosphor tin [66579-64-4] 2.5—3 wt % P, is made for the deoxidation of bronzes and German silver. 

Copper increases tensile strength and hardness and offers some protection against elements that promote intergranular corrosion. However, copper reduces impact strength and dimensional stabiUty owing to aging and is therefore kept at 1.25% max. 

The cast zinc—aluminum—copper slush alloy, after aging for ten years indoors, shows a tensile strength of 238 MPa (34,500 psi) with Charpy impact strengths of 1.4—4.1 J (1—3 ft4bf) (87). 

Greater amounts of copper increase the proportion of needles or stars of Cu Sn in the microstmcture. Increase in antimony above 7.5% results in antimony—tin cubes. Hardness and tensile strength increase with copper and antimony content ductiUty decreases. Low percentages of antimony (3—7%) and copper (2—4%) provide maximum resistance to fatigue cracking in service. Since these low alloy compositions are relatively soft and weak, compromise between fatigue resistance and compressive strength is often necessary. 

The effect of cold working by cold rolling of sheet on the yield, at 0.2% offset strain, and tensile strengths of copper sheet is shown in Figure 1. 

Fig. 1. The effect of cold rolling upon the tensile properties of unalloyed copper (CllO) (—) represents tensile strength (-...

Fig. 3. Changes in tensile properties of cold roUed copper (CllO), after 50% reduction in thickness, that attend annealing at each of the temperatures shown for one hour (—) represents tensile strength (---), the 0.2% yield strength and ( ), the tensile elongation. To convert MPa to psi, multiply by 145.

Properties of copper—tin—lead alloys are Hsted in Table 10. The members of the tin bronze alloy group are cast using the centrifugal, continuous, permanent, plaster, and sand molding methods. Leaded tin—bronze alloys have minimum tensile strengths of 234—248 MPa (34,000—36,000 psi) as cast in sand molds, whereas the minimum tensile strengths for high leaded tin—bronze alloys are 138—207 MPa (20,000—30,000). The values are based on measurement of test bars cast in sand molds. 

The alloys in the copper—siUcon group have been cast using centrifugal, investment, die, permanent, plaster, and sand molding methods. The minimum tensile strengths for sand-cast test bars are 310—413 MPa (45,000—60,000 psi). 

Brasses with up to 15 percent Zn are ductile but difficult to machine. Machinability improves with increasing zinc up to 36 percent Zn. Brasses with less than 20 percent Zn have corrosion resistance eqmvalent to that of copper but with better tensile strengths. Brasses with 20 to 40 percent Zn have lower corrosion resistance and are subject to dezincincation and stress-corrosion cracking, especially when ammonia is present. 

Copper and Alloys With few exceptions the tensile strength of copper and its alloys increases quite markedly as the temperature goes down. However, coppers low structural strength becomes a problem when constructing large-scale equipment. Therefore, alloy must be used. One of the most successful for low temperatures is sihcon bronze, which can be used to —I95°C (—320°F) with safety. 

The approximate tensile strength is 14 ton/in7 at ordinary temperatures, and its strength decreases with increasing temperature. Typical mechanical properties of copper as a function of temperature are given in Table 3.16. 

Copper retains high impact strength and increases its tensile strength under low temperatures, including cryogenic applications. Typical data are given in Table 3.17. 

These are alloys containing more than 50% of copper used to overcome the softness, low tensile strength and high casting temperature of the pure... 

Figure 3.5. Eflett of temperature on the tensile strength of copper (A) effect of annealing on strength and ductility (B) hardened high-conductivity copper 129. ...

Bnich-kupfer, n. scrap copper, -last, /. breaking load, -metall, n. broken metal, scrap metal, -modul, m. modulus of rupture, -probe, /. breaking test, breakdown test, -punkt, m. breaking point, -riss, m. (Meial.) failure crack, -silber, n. broken silver, scrap silver, -spaonung,/. breaking stress tensile strength, -stein, m. quarry stone broken stone, -stelle,/. broken place, place of fracture. -strich, m. (Math.) fraction stroke (between numerator and denominator), -stiick, n. fragment shred, -stiicke, pi. debris scrap, -teil, m. fraction, -zahl, /. fractional number. 

Nonmagnetic drill collars are manufactured from various alloys, although the most common are Monel K500 (approximately 68% nickel, 28% copper with some iron and manganese, and 316L austenitic stainless steel). A stainless steel with the composition of 0.06% carbon, 0.50% silicon, 17-19% manganese, less than 3.50% nickel, 12% chromium, and 1.15% molybdenum, with mechanical properties of 110 to 115 Ksi tensile strength is also used. 

Aluminum drillpipe is generally made of 2014 type aluminum-copper alloy. Composition of this alloy is 0.50 to 1.20% silicon, 1.00% iron maximum, 3.90 to 5.0% copper, 0.40 to 1.20% manganese, 0.25% zinc maximum and 0.05% titanium. The alloy is heat treated to T6 conditions that represent 64 ksi tensile strength, 58 Ksi yield strength, 7% elongation and a Hbn of 135- Aluminum drillpipe generally comes with steel tool joints that are threaded on to ensure maximum strength that cannot be attained with aluminum joints. 

The mechanical properties of wrought alloys depend on composition and metallurgical condition. At the extremes, annealed pure copper has a tensile strength of 180MN m and a hardness of 40 Hy, and heat-treated beryllium copper can have a tensile strength of 1 300 MN m and a hardness of 390 Hy. Summaries of typical properties of some of the more important wrought and cast copper alloys are given in Tables 4.9 and 4.10. 

In the tests described by Tracy, a high-tensile brass suffered severe dezinc-ification (Table 4.11). The loss in tensile strength for this material was 100% and for a non-arsenical 70/30 brass 54% no other material lost more than 23% during 20 years exposure. In Mattsson and Holm s tests the highest corrosion rates were shown by some of the brasses. Dezincification caused losses of tensile strength of up to 32% for a P brass and up to 12% for some of the a-P brasses no other materials lost more than 5% in 7 years. Dezinc-ification, but to a lesser degree, occurred also in the a brasses tested, even in a material with as high a copper content as 92%. Incorporation of arsenic in the a brasses consistently prevented dezincification only in marine atmospheres. 

In copper sulphate solutions, hardness and tensile strength are increased... 

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