High Carbon Steel

• EN9
• C50
• C55MN75

EN9 Steel

En9 steel is a medium carbon steel grade having carbon content within 0.5 to 0.6 commonly supplied in the as rolled condition. It is available in rounds, flats, hexagons and other forms. It is used in a number of engineering applications such as gears, sprockets and cams. It can be flame or induction hardened to produce a high surface hardness with excellent wear resistance for a carbon steel grade.

C50

It is a medium carbon steel is used when greater strength and hardness is desired than in the as rolled’ condition. C50 steel plate, EN 10083 C50 steel plate, under EN 10083 standard, we can regard C50 steel plate as high carbon steel. C50 steel plate is one mainly of high carbon steel, EN 10083 C50 steel plate is one of the higher carbon content (0.47-0.55) steels.

Soft Annealing

Heat to 680-710°C, cool slowly in furnace.

Normalising

Normalising temperature: 840-880°C/air.

Hardening

Harden from a temperature of 820-860°C followed by water or oil quenching.

Tempering

Tempering temperature: 550-660°C/air.

Forging

Hot forming temperature: 1050-850oC.

Applications

Soft Annealing: Heat to 680-710oC, cool slowly in furnace. Normalising: Normalising temperature: 840-880oC/air. Hardening: Harden from a temperature of 820-860oC followed by water or oil quenching. Tempering: Tempering temperature: 550-660oC/air. Forging: Hot forming temperature: 1050-850oC. Applications: Quenched and subsequently tempered steel for screws, forgings, wheel tires, shafts, sickles, axes, knives, wood working drills, hammers, etc.

Properties of grade C50 Weld-ability

Due to the medium-high carbon content it can be welded with some precautions.

Harden-ability

It has a low harden ability in water or oil; fit for surface hardening that gives this steel grade a high hardness of the hardened shell.

C55Mn75

Carbon steels are the steels having carbon as the major alloying element. They also contain up to 1.2% manganese and 0.4% silicon. In addition, the residual elements like copper, molybdenum, aluminium, chromium and nickel are present in these steels.
Applications Agricultural implements
Heavy machinery components
Wear-resistant parts
Ring-rolling tools
Battering tools
Hand tools
Springs
Heat Treatment
Normalise at 1550° to 1625°F (843° to 885°C)
Full anneal at 1525° to 1600°F (829° to 871°C) before furnace cooling
Process anneal at 1100° to 1225°F (593° to 663°C) after cold working
Harden
Heat to 1450° to 1525°F (788° to 829°C)
Oil or water quench
Temper
May be oil or water quenched
Mach-inability
Sulphured or chlorinated cutting oils for high-speed steel cutters
No oil for carbide-tip tools
Grind high-speed steel turning tools
8-12° side rake
6-10° back rake
7-9° side and end relief
12-16° side cutting-edge angle
8-14° end cutting-edge angle
Nose radius 10% of cut depth
Grind carbide-tip tools
6-12° side rake
2-8° back rake
6-10° side and end relief
8-12° end cutting-edge angle
8-16° side cutting-edge angel
1/32” nose radius
Work-ability
Hot work 2200° to 1800°F (1204° to 982°C)
Intermediate annealing required for considerable cold working
Fully anneal when further cold work will follow extensive cold work