Materials Produced

Ni Resist Cast Iron

Ni Resist castings can be specified in either a Grey Cast Iron base material or a SG Iron – Ductile Iron based material.  These materials have been developed to offer good resistance to sea water and alkaline corrosion, scaling resistance, thermal expansion, frictional wear, oxidation, structural stability, cryogenic applications and erosion.

 

SG Iron - Ductile Iron based material has the addition of certain alloys that enhance the performance of the material. Ni is the predominant addition element of between 18 and 37%. Ni Resist can also be used for applications were non magnetisable features are required.

 

The benefits of Ni Resist Cast Iron are:

 

Cost
When compared to stainless steel castings, Ni Resist castings can offer price advantages. Ni Resist castings are lighter than stainless steel castings. They can be cast near to final shape.

 

Machining

Ni Resist is easier to machine than stainless steel. Machining allowances are lower on Ni Resist castings when compared to stainless steel.

 

Weight

Ni Resist castings will weigh less than stainless steel castings.

 

Castability

As with Grey Cast Iron and SG Cast Iron, Ni Resist castings offer all of the design benefits associated with Iron Castings. Complex shapes can be accommodated, excellent surface finish will be achieved and complex designs can be undertaken.

 

 

Ni-Resist Specification BS3468 1986

Type	Grade	Chemical Composition
		C%max.	Si%	Mn%	Ni%	Cu%	Cr%	Nb%	P%max	Mg%
Flake Graphite	F1	3.0	1.5 - 2.8	0.5 - 1.5	13.5 - 17.5	5.5 - 7.5	1.0 - 2.5	-	0.2	-
	F2	3.0	1.5 - 2.8	0.5 - 1.5	18.0 - 22.0	0.5 max	1.5 - 2.5	-	0.2	-
	F3	2.5	1.5 - 2.8	0.5 - 1.5	28.0 - 32.0	0.5 max	2.5 - 3.5	-	0.2	-
Spheroidal Graphite	S2	3.0	1.5 - 2.8	0.5 - 1.5	18.0 - 22.0	0.5 max	1.5 - 2.5	-	0.08
	S2B	3.0	1.5 - 2.8	0.5 - 1.5	18.0 - 22.0	0.5 max	2.5 - 3.5	-	0.08	-
	S2C	3.0	1.5 - 2.8	1.5 - 2.5	21.0 - 24.0	0.5 max	0.5 max	-	0.08	-
	S2M	3.0	1.5 - 2.5	4.0 - 4.5	21.0 - 24.0	0.5 max	0.2 max	-	0.08	-
	S2W	3.0	1.5 - 2.2	0.5 - 1.5	18.0 - 22.0	0.5 max	1.5 - 2.2	0.12 - 0.2	0.05	0.06max*
	S3	2.5	1.5 - 2.8	0.5 - 1.5	28.0 - 32.0	0.5 max	2.5 - 3.5	-	0.08	-
	S5S	2.2	4.8 - 5.4	1.0 max	34.0 - 36.0	0.5 max	1.5 - 2.5	-	0.08	-
	S6	3.0	1.5 - 2.8	6.0 - 7.0	12.0 - 14.0	0.5 max	0.2 max	-	0.08	-

 

Austenitic Cast Iron Specifications in accordance with BS3486

Type	Grade	Tensile Strength (min) N/mm2	0.2% Proof Stress (info only)	Elongation % (info only)	Charpy V notch @ 20C (J)	Brinell Hardness BHN	Typical Properties/Uses
Flake Graphite	F1	170	-	1 - 2	-	140 - 220	Good corrosion and heat resistance combined with good bearing properties. Uses include Marine, furnace, pumps and valves.
	F2	170	-	1 - 3	-	140 - 220	Similar to F1 but has greater alkali corrosion resistance. For use in pumps for soap, food and plastics manufacture.
	F3	190	-	1 - 3	-	120 - 215	Erosion resistance in wet steam and salt slurry. Good thermal shock resistance up to 800c along with good high temperature corrosion resistance. Uses include Exhaust gas manifolds, turbocharger housings, filters, pumps and valves.
Spheroidal Graphite	S2	370	210	7 - 20	4 - 20	140 - 230	Corrosion and heat resistance similar to F1 but with superior mechanical properties. Typical uses include exhaust manifolds for use up to 750c, pumps, valves and turbocharger parts.
	S2B	370	210	7 - 20	4 - 10	140 - 230	Better corrosion resistance to that of grade S2 due to presence of Chromium but a harder alloy to ensure freedom from porosity in. Typical uses include exhaust manifolds for use up to 750c, pumps, valves and turbocharger parts.
	S2C	370	170	20 - 40	20 - 30	130 - 170	Non-magnetic with good impact properties down to -100c. Lower corrosion and heat resistance than S1. Typical uses include non-magnetic components for generator sets, insulator flanges and for moderate cryogenic applications.
	S2M	420	210	25 - 45	15 - 25	150 - 180	Non-magnetic with mechanical properties maintained down to -150c. Uses include cryogenic components for use down to liquid nitrogen temperatures.
	S2W	370	210	7 - 20	10 - 20	140 - 200	Corrosion and heat resistance similar to F1 but with superior mechanical properties. Typical uses include exhaust manifolds for use up to 750c, pumps, valves, and turbocharger parts. S2W has improved weldability compared with grade S2.
	S3	370	210	7 - 18	4 - 20	130 - 200	Similar to grade F3 but with enhanced mechanical properties. Uses include exhaust gas manifolds, turbocharger housings, filters, pumps and valves.
	S5S	370	210	7 - 20	-	130 - 180	Very good resistance to growth and scaling up to 850c combined with good thermal shock resistance. Used for turbocharger housings, support rings, exhaust gas manifolds and dieblocks for titanium pressings.
	S6	390	200	15 - 25	15 - 25	130 - 170	Non-magnetic, used for covers for turbine generator sets ducts and terminals.

* Magnesium is always an added element in S Grades, but the level is not specified except in the case of Grade S2W.