Cor-Ten castings

Conversion table of produced steels. We prefer to supply final product according to Chomutov marking. On special customer´s request is possible to supply castings according to other standard.

Marking of Chomutov	EU EN	WNr.	DE marked by DIN	FRA AFNOR	UK BSI	ITA UNI
GS-20Mn5	G20Mn5	1.1120	GS-20Mn5	280-480 M	161 Gr.540 A	FeG 52
G24Mn6	G24Mn6	1.1118	G24Mn6	-	-	-
ČSN 42 2709	G28Mn6	1.1165	G28Mn6	A 32-054	A 4	-
ČSN 42 2711	-	-	-	-	-	-
ČSN 42 2712	-	1.1120	GS-20Mn5	280-480 M	161 Gr.540 A	FeG 52
ČSN 42 2719	-	-	-	-	-	-
ČSN 42 2735	-	-	-	-	-	-
ČSN 42 2739	-	-	-	-	-	-
ČSN 42 2753	-	-	-	-	-	-
ON 42 2833	-	-	-	-	-	-
VP-7	-	-	-	-	-	-
VTS	-	-	-	-	-	-
G42CrMo4	G42CrMo4	1.7231	G42CrMo4	-	-	-

ČSN 42 2709 (Mn steel)

Chemical composition in percents

C	Mn	Si	P	S	P+S
0.20	1.20	0.20	max.	max.	max.
0.28	1.60	0.50	0.05	0.05	0.09

Castings are delivered as normalized (+N) or normalized and tempered (+NT). Hardening treatment of this quality is not performed.

Mechanical properties and values

Tensile strength	Rm	N/mm2	520 - 670
Yield point Rp 0.2	Re	N/mm2	≥ 300
Elongation	A	%	≥ 18
Contraction	Z	%	≥ 25
Notch impact toughness KCU3	KC	J/cm2	≥ 39
Hardness	-	HB	149 - 184

• Weldability
  Guaranteed under specific conditions - preheating to 250°C. After welding, it is recommended to anneal at 600-630°C for the stress relieving.
• Machinability
  Very good when normalized and tempered. Good in heat-treated condition.
• Application
  For parts subjected to greater stresses with higher toughness, for example track shoe of tractors, etc. The steel has a good hardenability and is capable even for surface flame hardening.

ČSN 42 2712 (Mn steel)

Chemical composition in percents

C	Mn	Si	P	S	P+S	Cr	Ni	Cu	Cr+Ni+Cu
0.17	0.90	0.20	max.	max.	max.	max.	max.	max.	max.
0.25	1.40	0.50	0.04	0.04	0.07	0.30	0.40	0.30	0.90

Castings are delivered as normalized and tempered (+NT). Considering intended use, this steel is not heat-treated exceptionally.

Mechanical properties and values

Tensile strength	Rm	N/mm2	500 - 650
Yield point Rp 0.2	Re	N/mm2	≥ 280
Elongation	A	%	≥ 20
Contraction	Z	%	>= 25
Notch impact toughness KCU3	KC	J/cm2	>= 50
Hardness	-	HB	140 - 183

• Weldability
  Guaranteed - up to a thickness of 25 mm. Guaranteed under specific conditions - over 25 mm in thickness preheating to 200°C. After welding, it is recommended to anneal at 590-620°C for the stress relieving.
• Machinability
  Very good.
• Application
  For cast parts of steam boilers and turbines, pressure tanks, steam and water pipes, plumbing fittings, highly stressed machine parts and welded pieces up to 450°C operating temperatures where high toughness is required.

ČSN 42 2719 (Si steel)

Chemical composition in percents

C	Mn	Si	P	S	P+S
0.52	0.50	0.50	max.	max.	max.
0.60	0.80	0.70	0.045	0.045	0.080

Castings are delivered as normalized and tempered (+NT). Hardening treatment of this quality is not performed.

Mechanical properties and values

Tensile strength	Rm	N/mm2	700 - 850
Yield point Rp 0.2	Re	N/mm2	>=340
Elongation	A	%	>= 10
Hardness	-	HB	197 - 237

• Weldability
  Good - preheating to 350°C. After welding, the casting must be annealed at 620-650°C for the lowering of stress. After annealing the castings must be allowed to cool in the furnace. Welding or welding up of flaws in critical and exposed places is not recommended.
• Machinability
  Good, by a lowered cutting speed.
• Application
  The steel is intended for higher pressures and stresses, e.g. gears of lower weight, ring gear, etc. It is not suitable for surface flame hardening.

G42CrMo4 (Cr-Mo steel)

Chemical composition in percents

C	Mn	Si	P	S	Cr	Mo
0.38	0.50	0.20	max.	max.	0.70	0.15
0.45	0.80	0.50	0.035	0.035	1.00	0.25

Castings are delivered as normalized (+N).

• Weldability
  Good - preheating to 350°C. After welding, the casting must be normalized is necessary. Welding or welding up on functionally exposed places is not recommended.
• Machinability
  Good – as normalized
  Difficult - when is hardening treated
• Application
  As normalized for gear and travel wheels of cranes and other highly stress machine parts.

VTS (Cr-Ni-Mo Steel)

Chemical composition in percents

C	Mn	Si	P	S	Cr	Ni	Mo
0.25	max.	0.50	max.	max.	2.00	2.75	0.30
0.35	1.00	1.00	0.04	0.04	2.50	3.25	0.50

The castings are usually not intended for cutting operation, but for direct use. They are delivered as hardening treated (QT). Exceptionally soft annealed (+A).

Mechanical properties and values

Tensile strength	Rm	N/mm2	*) max. 880	**) 1400 - 1600
Yield point Rp 0.2	Re	N/mm2	-	**) >=1020
Elongation	A	%	-	**) >= 8
Contraction	Z	%	*) >= 30	-
Notch impact toughness KCU3	KC	J/cm2	-	**) >= 23
Hardness	-	HB	*) 214 - 258	**) 406 - 458

*) in condition soft annealed
**) in condition hardened treated

• Weldability
  Good under specific conditions - preheat to 150°C. Apply short interrupted weld beads. Forge immediately weld metal. Ensure very slow cooling. The material is not recommended to welding.
• Application
  For forms for injection moulding.
  For its high strength and toughness, the steel is also suitable for excavators teeths and castings where is required high resistance to the dynamic forces connected with contemporary impacts and high abrasion.
  The steel is greatly self-hardenable on air.

VP-7 (Mn-Cr-Mo-V steel)

Chemical composition in percents

C	Mn	Si	P	S	Cr	Mo	Mo
0.25	1.40	0.20	max.	max.	0.60	0.15	0.05
0.32	1.80	0.60	0.04	0.04	0.90	0.50	0.15

The steel is micro-alloyed with Ti and B. The castings are only delivered as hardening treated (+QT) for direct use and are not intended for cutting operation.

Mechanical properties and values

Tensile strength	Rm	N/mm2	1200 - 1500
Yield point Rp 0.2	Re	N/mm2	>=950
Elongation	A	%	>= 2
Contraction	Z	%	>= 4
Notch impact toughness KCU3	KC	J/cm2	>= 15
Impact energy	K	J	>= 10
Hardness	-	HB	340 - 420

• Weldability
  Good to difficult - preheating to 250°C is required.
  After welding or welding up of the surface flaws, it is necessary to provide a slow cooling down or to be again heat-treatment.
  This steel is not intended for welding. The critical limit of tempering brittleness lies around 300-450°C.
• Machinability
  Very difficult. When machining is necessary, soft annealing is more preferable (strength Rm = 700-1000 N/mm2 and hardness HB = 250-300). Subsequently heat-treated.
• Application
  Very suitable for the production of excavator teeth, socket of bucket, rock blades, etc. Wherever increased resistance to plastic deformation under simultaneously impact of dynamic forces and impact and resistance to abrasion is required. The steel is eligible for local thermal reprocessing of castings parts to a higher hardness.

ON 42 2833 (Eutectoid Cr-W Steel)

Chemical composition in percents

C	Mn	Si	P	S	Cr	W
0.78	0.65	max.	max.	max.	1.40	0.90
0.88	0.85	0.50	0.05	0.05	1.60	1.40

The castings are delivered only as soft annealing (+A) for using to cutting operation.
The castings, that are not intended to cutting operation, but used directly, are delivered as hardened (+QT) to lower values. The smaller castings can be hardened to higher values only on agreement.

Mechanical properties and values

Hardening treatment at lower values is carried out by air hardening, at higher values by oil hardening. The foundry has not its own oil bath at disposal.

Tensile strength	Rm	N/mm2	+) 785 - 875	*) 1030 - 1130	**) 1700 - 1850
Yield point Rp 0.2	Re	N/mm2	-	*) >=700	**) >=1100
Elongation	A	%	-	*) >= 8	**) >= 2
Contraction	Z	%	-	*) >= 16	**) >= 4
Notch impact toughness KCU3	KC	J/cm2	-	*) >= 18	**) >= 6
Impact energy	K	J	-	*) >= 11	**) >= 4
Hardness	-	HB	+) 225 - 250	*) 312 - 345	**) 460 - 520

+) as soft annealed
*) in condition hardened to lower values
**) in condition hardened to higher values

• Weldability
  Difficult. The welding is not recommended!
• Machinability
  Difficult in soft annealed condition. In hardened condition is possible only by grinding.
• Application
  Basically it is a tool steel with a wide application for simple, bulky cast tools to be used for cold and warm works. The rolls for rolling mills up to 300 mm diameter, dies, punches, blades for hydraulic shears for scrap, tools for pressure castings does not achieve the level of those in the formed steel.
  The mechanical properties allow application in production of various parts under wear resistant conditions.
  Higher values than those given above are not recommended., although the material is capable to achieve them. Such castings could be destructed.