公开(公告)号：US12128474B2

公开(公告)日：2024-10-29

申请号：US18037783

申请日：2022-09-05

Applicant: NANJING UNIVERSITY OF AERONAUTICS AND ASTRONAUTICS

Inventor： Haoqin Yang ,  Zhongde Shan ,  Qinjiang Liu ,  Jianpei Shi ,  Dandan Yan ,  Shijie Dong

IPC: B22C9/12 ,  B22C9/03

CPC classification number: B22C9/126 ,  B22C9/03

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.