US 12,134,123 B2
Use of a coating composition and corresponding method for producing a centrifugal casting mould with a coating
Sven Hennig, Barsinghausen (DE); Andreas Jattke, Hannover (DE); and Klaus Seeger, Hannover (DE)
Assigned to HÜTTENES-ALBERTUS Chemische Werke Gesellschaft mit beschränkter Haftung, Düsseldorf (DE)
Appl. No. 17/268,015
Filed by HÜTTENES-ALBERTUS Chemische Werke Gesellschaft mit beschränkter Haftung, Düsseldorf (DE)
PCT Filed Aug. 13, 2019, PCT No. PCT/EP2019/071659
§ 371(c)(1), (2) Date Feb. 11, 2021,
PCT Pub. No. WO2020/035474, PCT Pub. Date Feb. 20, 2020.
Claims priority of application No. 102018119635.0 (DE), filed on Aug. 13, 2018; and application No. 102018131811.1 (DE), filed on Dec. 11, 2018.
Prior Publication US 2021/0178459 A1, Jun. 17, 2021
Int. Cl. B22C 3/00 (2006.01); B05D 1/02 (2006.01); B22C 9/06 (2006.01); B22D 13/10 (2006.01); C04B 35/48 (2006.01); C04B 35/482 (2006.01); C04B 35/622 (2006.01)
CPC B22C 3/00 (2013.01) [B05D 1/02 (2013.01); B22C 9/06 (2013.01); B22D 13/102 (2013.01); C04B 35/481 (2013.01); C04B 35/482 (2013.01); C04B 35/62222 (2013.01); C04B 2235/3248 (2013.01); C04B 2235/3418 (2013.01); C04B 2235/422 (2013.01); C04B 2235/528 (2013.01); C04B 2235/5436 (2013.01)] 22 Claims
 
1. A method of producing a refractory coating on the inner walls of a centrifugal casting mold by means of a spray application of a refractory coating composition, wherein the refractory coating composition has:
a solids fraction of more than 69 wt %, based on the total mass of the coating composition, and
a loss on ignition of less than 0.6 wt %, based on the total mass of the solids fraction of the coating composition,
wherein the refractory coating composition is a dispersion of refractories in an aqueous phase, the refractories at least comprising
(a) a total amount in the range from 4 to 50 wt % of particulate amorphous oxide, based on the total mass of the coating composition,
wherein the particulate amorphous oxide comprises a fraction of 85 wt % or more of silicon dioxide, based on the total amount of the particulate amorphous oxide,
wherein the particulate amorphous oxide possesses a mass-based D95 of less than 5 μm, determined by laser diffraction,
wherein the particulate amorphous oxide possesses a porosity of less than 50%, based on the total amount of the particulate amorphous oxide, and
wherein 90 wt % or more of the particles of the particulate amorphous oxide possess a sphericity of greater than 0.9, determined by evaluating two-dimensional microscope images, or
a total amount in the range from 4 to 50 wt % of microsilica as particulate amorphous oxide, based on the total mass of the coating composition, and
(b) one or more further refractories,
wherein 98 wt % or more of the total mass of the refractories are capable of passing through a sieve having a mesh size of 0.75 mm.