Austempered Ductile Iron is also referred to as ADI. This material has been developed to offer enhanced strength and wear resistant properties. Impact resistance of Ductile Iron is retained. This material also offers enhanced fatigue properties.

Post casting austempering is an isothermal heat treatment applied to SG Iron materials. The chemical analysis of the SG Iron has to be controlled very carefully to ensure that the maximum mechanical properties resulting from the post casting solution treatment are achieved.

Additions of copper, nickel and molybdenum are made to improve hardenability. Austempered Ductile Iron (ADI) is being used for demanding applications and is replacing carbon steel castings and forged components due to the following benefits:

Cost

When compared to carbon steel castings and steel forgings and fabrications ADI – Austempered Ductile iron has a lower manufacturing cost.

Castability

ADI has a lower casting temperature than steel and this allows for a superior surface finish and the ability to cast complex shapes incorporating changes of section.

Tensile Strength

1600 N/mm2 can be achieved with certain grades of Austempered Ductile Iron.

Weight Saving

ADI has a lower density than steel. Casting designs incorporate near net shape offering significant weight savings over steel castings.

Improved Noise Damping

The presence of graphite in the Austempered Ductile Iron improves noise damping.

Superior Wear and Abrasion Resistance

The wear characteristics of ADI improve in service. Hardening occurs during normal operational use. Therefore ADI is a perfect choice high abrasion application.

Machining

The ability to cast to near net shape reduces the machining costs of ADI castings when compared to steel products.

		Material designation; symbol and (number)
		EN-GJS-800-8(EN-JS1100)	EN-GJS-1000-5(EN-JS1110)	EN-GJS-1200-2(EN-JS1120)	EN-GJS-1400-1 (EN-JS1130)
Characteristic	Unit	Minimum values for properties 1) (normative)
Tensile Strength Rm	N/mm2	800	1000	1200	1400
0.2% proof stress R po.2	N/mm2	500	700	850	110
Elongation A	%	8	5	2	1
Impact resistance valuesCharpy notched, at (23±5) °C	J	10	2) mean value of 3 tests
		9	3) individual value
		Minimum values for properties 1) (informative)
Compression strength	N/mm2	1300	1600	1900	2200
0.2% proof stress	N/mm2	620	770	1040	1220
Shear strength	N/mm2	720	900	1080	1260
Torsional strength	N/mm2	720	900	1080	1260
0.2% proof stress	N/mm2	350	490	590	770
Impact resistance valuesCharpy notched, at (23±5) °C	J	100	80	60	30
Fracture tougness K	Mpa-m 1/2	62	58	54	50
Fatigue limit (Wöhler)(rotating bending) unnotched(dia. 10.6mm)	N/mm2	375	425	450	375
Fatigue limit (Wöhler)(rotating bending) notched 4)(dia. 10.6mm)	N/mm2	225	260	280	275
		Typical Values
Brinell hardness	HN	260 to 320	300 to 360	340 to 440	380 to 480
Modulus of elasticity E	kN/mm2	170	168	167	165
Poisson’s ratio v	–	0.27	0.27	0.27	0.27
Shear modulus	kN/mm2	65	64	63	62
Density p	kg/dm3	7.1	7.1	7.1	7.1
Linear expansioncoefficient a	mm/(m.K)	14.6	14.3	14	13.8
Thermal conductivity	W/(m.K)	22.1	21.8	21.5	21.2

Note 1: The mimimum values can be obtained on wall thickness up to 50mm. For heavier sections agreement between purchaser and manufacturer is recommended.

Note 4: Notched after heat-treatment.