Kathleen M Lowe

US Patent:

20180001372, Jan 4, 2018

Filed:

Dec 14, 2016

Appl. No.:

15/545388

Inventors:

- Wilmington DE, US
Gregory P. STURTZ - Dublin OH, US
Kathleen E. LOWE - Powell OH, US
Joerg KROKER - US OH, US

International Classification:

B22C 1/08
C04B 35/628
B22C 9/02

Abstract:

A molding material mixture for producing casting molds for metal processing, particularly for non-ferrous metals, such as aluminum or magnesium, is intended to reduce problems such as metal-mold reaction and/or shrinkage porosity defect. The free-flowing refractory molding material in the molding material mixture is coated with a mixture of inorganic salts exhibiting a eutectic melting point in the range of about 400 C to about 500 C, particularly in the range of about 420 C to about 460 C. Preferably this coating occurs by contacting the inorganic salt mixture with the molding material mixture at a temperature between 500 C and 700 C, in a manner that maintains the free-flowing nature of the coated product. One mixture of inorganic salts that is used is a mixture consisting of, by weight: 74% potassium fluoroborate; 15% potassium chloride; and 12% potassium fluoride. This mixture has a eutectic melting point of 420 C.