James F. Bredt - Watertown MA,
Michael J. Tarkanian - Brockton MA,
Mahati Chintapalli - Minnetonka MN,
Massachusetts Institute of Technology - Cambridge MA
Mixture for use in a three-dimensional printer to make molds suitable for producing ferrous coatings. The mixture includes cement, sand and accelerator. Grain sizes of the cement, sand and accelerator are selected to assure that the three-dimensional printer generates coherent layers.