| CPC B22C 9/10 (2013.01) [B22C 1/02 (2013.01)] | 23 Claims |
|
1. A casting core for casting molds, comprising:
an inner core; and
an outer core located around the inner core;
wherein the outer core includes multiple ceramic particles bound using a binder, wherein the inner core includes multiple ceramic particles bound using a binder, and wherein the multiple ceramic particles of the inner core comprise at least one of:
at least one component that has a thermally induced phase change at a temperature in a range of 100° C. to 1500° C., inclusive; or
at least two components having coefficients of thermal expansion that, at 20° C., differ from one another by at least 5·10−6K−1;
wherein the outer core does not comprise any component that has a thermally induced phase change at a temperature in a range of 100° C. to 1500° C., and wherein the outer core does not comprise two components having coefficients of thermal expansion that, at 20° C., differ from one another by at least 5·10−6K−1.
|
|
17. A method for producing a casting core, the method comprising:
producing a first aqueous ceramic suspension, the first aqueous ceramic suspension including multiple ceramic particles, a binder, and water;
producing a second aqueous ceramic suspension, the second aqueous ceramic suspension including multiple ceramic particles, a binder, and water;
solidifying the first aqueous ceramic suspension to form an inner core of the casting core;
drying the solidified first aqueous ceramic suspension;
solidifying the second aqueous ceramic suspension to form an outer core of the casting core; and
drying the second aqueous ceramic suspension;
wherein the multiple ceramic particles of the first aqueous ceramic suspension include at least one of:
at least one component that has a thermally induced phase change at a temperature in a range of between 100° C. and 1500° C., inclusive; or
at least two components having coefficients of thermal expansion that, at 20° C., differ from one another by at least 5·10−6K−1;
wherein the outer core does not comprise any component that has a thermally induced phase change at a temperature in a range of 100° C. to 1500° C., and wherein the outer core does not comprise two components having coefficients of thermal expansion that, at 20° C., differ from one another by at least 5·10−6K−1.
|
|
22. A casting core for casting molds, comprising:
an outer core; and
an inner core;
wherein the outer core includes a first set of ceramic particles bound using a first binder, wherein the outer core does not comprise any component that has a thermally induced phase change at a temperature in a range of 100° C. to 1500° C., wherein the outer core does not comprise two components having coefficients of thermal expansion that, at 20° C., differ from one another by at least 5·10−6K−1, wherein the inner core includes a second set of ceramic particles bound using a second binder, wherein the second set of ceramic particles comprise at least one of: at least one component that has a thermally induced phase change at a temperature of between 100° C. and 1500° C., inclusive, or at least two components having coefficients of thermal expansion that, at 20° C., differ from one another by at least 5·10−6K−1, wherein the first set of ceramic particles are at least one of: zircon sand particles, aluminosilicate particles, mullite particles, inorganic hollow microspheres, alumina particles, or mixtures thereof, wherein at least one of the first set of ceramic particles or the second set of ceramic particles have a mean particle diameter of between 0.5 μm and 500 μm, inclusive, wherein at least one of the binder of the inner core or the binder of the outer core include at least one of an inorganic binder, an organic binder, or a mixture thereof, wherein the at least one component has a thermally induced phase change at a temperature in a range between 100° C. to 1500° C., inclusive, and wherein the at least one component is at least one of quartz, cristobalite, or a mixture thereof.
|