Abstract: An ultrasonic-assisted permeation and homogenization molding device and method for frozen printing liquid drops are provided. The device includes an ultrasonic generator, a transducer and an amplitude-change pole. The ultrasonic generator generates 20 KHz low-frequency ultrasonic waves, and a flange plate is arranged on a pitch surface of the amplitude-change pole and connected with an outer cavity wall of the low-temperature molding chamber by threads. According to the ultrasonic-assisted permeation and homogenization molding method for frozen printing liquid drops, pre-paved molding sand particles are homogenized and distributed under ultrasonic vibration by adjusting the frequency of the ultrasonic generator in a sand paving process. When a pure water binder is sprayed, liquid drops are sprayed to the surface of premixed molding sand, and then permeate to the bottom of pre-cooled molding sand under the assistance of low-frequency ultrasonic waves to freeze and solidify.

Abstract: A low-temperature airflow follow-up auxiliary sand discharge apparatus for cutting a frozen sand mold includes a frozen sand mold to be machined, a hollow cutter, a spindle mounted on the hollow cutter, an air pipe, and a refrigeration apparatus connected to one end of the air pipe. The refrigeration apparatus is fixed to an air pump by a valve. An inner cavity of the hollow cutter is provided with a cutter through hole along an axis. An inner cavity of the spindle is provided with a spindle through hole along the axis. An upper end of the spindle is provided with a bearing seat hole for placing a bearing. An outer circle of the bearing matches the bearing seat hole, and an inner circle of the bearing is mounted with an air pipe connector. The air pipe is connected and fixed to the air pipe connector.

Abstract: A method for preparing a negative pressure film-covering frozen sand mold includes: directly obtaining a mold cavity of a sand mold through numerically controlled machining of a frozen sand blank; covering a surface, brushed with a thermal insulation coating, of the mold cavity of the sand mold with a softened thin film, and covering an outer surface of the sand mold with a back film to seal a sand box; fixing the frozen sand mold in an air extraction sand box with a vacuum chamber, and extracting air through a vacuum pump, so that the thin film tightly adheres to the sand mold through vacuum suction force; and closing the box to obtain an integral sand mold, and pouring a casting at room temperature or low temperature under negative pressure. The method is environment-friendly, and the prepared frozen sand mold has high strength and is convenient for sand cleaning.