received by the International Bureau on 13 June 2016

1. A cast iron composition consisting of:

from about 2.0 to about 4.0 wt % aluminum;

from about 2.0 to about 4.3 wt % silicon, with the proviso that an equivalent silicon amount, defined as silicon content plus 0.8 times aluminum content, be greater than about 4.7 wt %, wherein a ratio of the amount of silicon to the amount of aluminum is from 1.1:0.9 to 0.9: 1.1; greater than about 1.5 wt % carbon, with the proviso that an equivalent carbon amount, defined as carbon content plus one-third of combined silicon and phosphorous content, be less than about 5.2 wt %;

from about 0.2 to about 1.1 wt % molybdenum;

less than about 0.03 wt % sulfur;

less than 0.005 wt % oxygen;

less than 0.10 wt % phosphorous;

less than about 0.30 wt % manganese;

less than 0.50 wt % nickel;

less than 0.15 wt % of rare earth metals, optionally being cerium or lanthanum; and a balance of iron, and inevitable/unavoidable impurities,

wherein the term "about" is defined as a variance up to 5% with respect to the stated value.

2. The composition of claim 1, consisting of from about 2.5 wt % to about 3.5 wt % aluminum.

3. The composition of claim 2, consisting of about 3.0 wt % aluminum.

4. The composition of claim 1, consisting of from about 2.5 wt % to about 3.8 wt % silicon.

5. The composition of claim 4, consisting of about 3.2 wt % silicon.

6. The composition of claim 1, consisting of about 0.4 wt % to about 0.9 wt %

molybdenum.

7. The composition of claim 6, consisting of about 0.6 wt % molybdenum.

8. The composition of claim 1, consisting of greater than about 2.0 wt % carbon.

9. The composition of claim 1, wherein the equivalent silicon amount is greater than about 5.0 wt %.

10. The composition of claim 9, wherein the equivalent silicon amount is greater than about 5.2 wt %.

11. The composition of claim 1 , wherein the equivalent carbon amount is less than about 4.7 wt %.

12. The composition of claim 11, wherein the equivalent carbon amount is less than about 4.2 wt %.

13. The composition of claim 1, wherein the ratio of the amount of silicon to the amount of aluminum is about 1.0: 1.0, wherein the equivalent silicon amount is greater than about 5.2 wt %, wherein the equivalent silicon amount is less than about 4.2 wt %, and wherein the composition is more narrowly defined as:

from about 2.5 wt % to about 3.5 wt % aluminum;

from about 2.5 wt % to about 3.8 wt % silicon; and

from about 0.4 wt % to about 0.9 wt % molybdenum.

14. A cast article formed of a material that comprises a cast iron composition, wherein the cast iron composition consists of:

from about 2.0 to about 4.0 wt % aluminum;

from about 2.0 to about 4.3 wt % silicon, with the proviso that an equivalent silicon amount, defined as silicon content plus 0.8 times aluminum content, be greater than about 4.7 wt %, wherein a ratio of the amount of silicon to the amount of aluminum is from 1.1:0.9 to 0.9: 1.1; greater than about 1.5 wt % carbon, with the proviso that an equivalent carbon amount, defined as carbon content plus one-third of combined silicon and phosphorous content, be less than about 5.2 wt %;

from about 0.2 to about 1.1 wt % molybdenum;

less than about 0.03 wt % sulfur;

less than 0.005 wt % oxygen;

less than 0.10 wt % phosphorous;

less than about 0.30 wt % manganese;

less than 0.50 wt % nickel;

less than 0.15 wt % of rare earth metals, optionally being cerium or lanthanum; and a balance of iron, and inevitable/unavoidable impurities,

wherein the term "about" is defined as a variance up to 5% with respect to the stated value.

15. The cast article of claim 14, wherein the cast article comprises an automotive exhaust component selected from the group consisting of: exhaust manifolds and catalytic converter cans; a turbocharger component selected from the group consisting of: turbine housings and center housings; an engine component selected from the group consisting of blocks, heads, cylinder liners, cam shafts, crank shafts, dampers, bed plates, valve train components, pistons, piston inserts, bearing caps, and pump housings; or a transmission component selected from the group consisting of: cases, carriers, housings, barring caps, fly wheels, and pump housings.

16. The cast article of claim 14, consisting of from about 2.5 wt % to about 3.5 wt % aluminum.

17. The cast article of claim 14, consisting of from about 2.5 wt % to about 3.8 wt % silicon.

18. The cast article of claim 14, consisting of about 0.4 wt % to about 0.9 wt %

molybdenum.

19. The cast article of claim 14, consisting of greater than about 2.0 wt % carbon.

20. The cast article of claim 14, wherein the equivalent silicon amount is greater than about 5.2 wt %, wherein the equivalent carbon amount is less than about 4.7 wt %, and wherein the ratio of the amount of silicon to the amount of aluminum is about 1.0: 1.0, and wherein the composition is more narrowly defined as:

from about 2.5 wt % to about 3.5 wt % aluminum;

from about 2.5 wt % to about 3.8 wt % silicon; and

from about 0.4 wt % to about 0.9 wt % molybdenum.