A little abut copper and its alloys.......

1. SEMINAR COPPER AND ITS ALLOYS bysooraj.v.rgectcr

2. INTRODUCTION

4. COPPER Non ferrous metal Good formability Softness Attractive and good colour Cold working characteristics Special electrical properties Magnetic properties Easy castability Low coefficient of friction Atmospheric corrosion resistance Low density

5. COPPER

6. COPPER ALLOYS (a)High conductivity copper (electrolytic) 99.9%copper 0.40% oxygen ,lead and iron less than 0.005% . silver 0.002%and Bi less than 0.001%. Electrolyte copper is used for electrical purpose. (b) Deoxidised copper 99.85% copper, less than 0.05% As,0.003% iron, and 0.003% Bi. Other elements may be of the order of 0.005% P, 0.01% lesd,0.10% Ni,0.003%and 0.005% Ag and Sb respectively

7. (c) Arsenical deoxidised copper 0.4% As, 0.04% P and remaining copper . It is used for welded vessels and tanks (d) Arsenical touch pitch copper 0.4% As,0.065% oxygen,0.02% Pb,0.15% Ni, 0.006% Ag,0.01% Sb and less than 0.005% Bi ,less than 0.020% Fe and remaining copper. (e) Oxygen free copper 0.005% Pb, 0.001% Ni, 00.001% Ag and less than 0.0005% and 0.001% Fe and Bi respectively. It is melted and cast in non oxidising atmosphere.

8. APPLICATION OF COPPER For making electrical parts, Heat exchangers, Screw maching products, For making various copper alloys, such as brass and bronze, For household utensils, etc

9. BRASS Brasses contain zinc as the principle alloying element. brasses are sub divided in to three groups; Cu-Zn alloys Cu-Pb-Zn alloys or leaded brasses Cu-Zn-Sn alloys or tin brasses Brasses are high resistance to corrosion and it is easily machinable. It also act as good bearing material. Zinc in the brass increases the ductility along with strength. Brass prossesses greater strength than copper , however it has a lower thermal and electrical conductivity..

10. BRASS

11. TYPES OF BRASSS (1) Giliding metal 5% to Zn (balance copper) and posses shades of colour from the red of a brassy yellow. Gliding metal is used for making coins, medals, tokens, fuse caps etc (2) cartridge brass 70% Copper and 30% zinc. In the fully annealed condition it has strength of over 300N/mm2. caps of electric lamp bulbs, door furniture etc. This brass, harden when deformed in the cold An annealing temperature of about 6000C is satisfactory in the most cases. (3) Admiralty brass Cu 71%, Zn 28% and Sn 1%. used for the tubes and other parts of condenser cooled by fresh water and for many other purpose.

12. (4) Aluminium brass 76% Cu, 22% Zn and 2% Al, a little arsenic is added to inhibit dezincification. (5)Basis brass 61.5-64%, the remainder being zinc.Used for press work where a relatively cheap material is required and the main commercial forms are sheet, strips and wire. (6)Muntz metal or yellow metal 60% of copper and 40% of zinc and is essentially a hot working material. ship sheathing, perforated metal, valve stems, condenser tubes, architecture works etc

13. BRONZE An alloy of copper and elements other than nickel or zinc.bronze is baisicaly an alloy of copper and tin. It possesses superior mechanical properties and corrosion resistance than brass. it is comparatively hard and it resist surface wear. It can be rolled in to wire, rod, and sheets

14. TYPES OF BRONZE (1) Phosphor bronze The most important copper-tin alloys are those which have been deoxidized with phosphorus during the refining process and hence are known as phosphor bronze. A phosphor (2)Aluminium bronze 89% Cu, 7% Al, and 3.5% Sn. It possess the following properties, good strength, high corrosion resistance, good heat resistance, good cold working properties etc (3)Silicon bronze 1-4% si,0.5-1.0% iron, 0.25-1.25% Mn, and balance amount of copper. When lead added as 0.05% improves machinability. It possess high strength and toughness as that of mild steel and corrosion resistance as that of copper.,

15. GUN METAL Gun metal is an alloy of copper, tin and zinc. Zinc cleans the metal and increase its fluidity. A small amount of lead may be added to improve castability and machinability.

16. TYPES OF GUN METAL (a)Admirality gun metal % of Sn,2% Zn,1.5% Pb,1.5% Ni, and balance Cu. It has tensile strength of 260-340 N/mm2. It is widely used for pumps, valves and miscellaneous castings and is also used for statuary. (b)Nickel gun metal 7% Sn, 2.25% Zn, 0.3% Pb, 5.5% Ni and balance copper. When sand cast and heat treated it has a tensile strength of 430-480 N/mm2. (c)Leaded gun metal 5% Sn, 5% Zn, 5% Pb, 2.0% Ni. When sand cast it has a tensile strength of 200-270 n/mm2. Gun metal is used for bearings, steam pipe fittings, hydraulic valve and gears, marine casting.

17. THANKS…