Casting molds, manufacture and use methods

1. A casting process comprising:

heating a casting mold in a furnace, the mold comprising:

a shell extending from a lower end to an upper end and having:

an interior space for casting metal; and

an opening for receiving metal to be cast;

pouring said metal into the interior space, the pouring comprising:

a first pouring of a first alloy; and

a second pouring of a second alloy;

withdrawing the mold from the furnace; and

during the withdrawing:

measuring a temperature of the mold; and

determining a position of the mold; and

determining a vertical position of a mushy zone, wherein the second pouring commences when the mushy zone has reached a target level.

2. The method of claim 1 performed repeatedly wherein:

parameters are iterated to achieve a desired value of a proxy for a vertical span of a mushy zone.

3. The method of claim 2 further comprising:

inspecting a produced casting by measuring a content of an element present in different contents in the first alloy and the second alloy.

4. The method of claim 3 wherein:

the measuring the temperature of the mold comprises using thermocouples each having a junction exposed to the interior space.

5. The method of claim 4 wherein:

the proxy is the vertical distance the mold passes from when a solidus front passes a thermocouple to when a liquidus front passes the thermocouple.

6. A method for estimating parameters of a transition zone between two alloys in a casting, the two alloys being respectively from a first pour and a second pour, the method comprising:

measuring a temperature of at least one location on a mold during withdrawal of the mold from a furnace;

determining when a solidus reaches said at least one location;

determining when a liquidus reaches said at least one location; and

based on movement of the liquidus relative to a surface of the first pour, determining when the second pour should commence.

7. The method of claim 6 wherein:

the measuring the temperature of the mold comprises using a vertical array of thermocouples on a part-forming cavity of the mold.

8. The method of claim 7 performed repeatedly wherein:

the thermocouples each have a junction exposed to the interior of the part forming cavity.

9. The method of claim 8 wherein:

parameters are iterated to achieve a desired position and span of the transition zone.

10. The method of claim 9 further comprising in one or more of the iterations:

a first pouring of a first alloy; and

a second pouring of a second different alloy.

11. The method of claim 6 wherein:

the measuring the temperature of the mold comprises using a plurality of thermocouples at different vertical positions on a part-forming cavity of the mold.

12. The method of claim 11 wherein:

there are at least five said thermocouples at five different vertical positions.

13. The method of claim 11 wherein:

at least five of the thermocouples are evenly vertically spaced from each other.

14. The method of claim 11 wherein:

there are at least two sets of thermocouples, each set having a thermocouple at the same height as a corresponding thermocouple of the other set.

15. A method for estimating parameters of a transition zone between two alloys in a casting, the method comprising repeating:

pouring of at least one alloy;

measuring a temperature of at least one location on a mold during withdrawal of the mold from a furnace;

determining when a solidus reaches said at least one location; and

determining when a liquidus reaches said at least one location,

wherein the repeating comprises:

iterating parameters to achieve a desired position and span of the transition zone, in one or more of the iterations the pouring comprising:

a first pouring of a first alloy; and

a second pouring of a second alloy.

16. The method of claim 15 wherein:

the measuring is by a plurality of thermocouples vertically-spaced from each other.

17. The method of claim 16 wherein:

there are at least five said thermocouples at five different vertical positions.

18. The method of claim 16 wherein:

at least five of the thermocouples are evenly vertically spaced from each other.

19. The method of claim 16 wherein:

there are at least two sets of thermocouples, each set having a thermocouple at the same height as a corresponding thermocouple of the other set.

20. The method of claim 16 further comprising:

calculating a cooling rate at each thermocouple.