This article elaborates the successful use of quickly adding supplement pressure technology from theory to practice which is used in the counter——pressure cast process. According to the principle of conter-pressure cast and on the bae of traditional steady pressure crystal technology

aiming at the improvement of its disadvantages

the article advances a new concept that is quickly adding supplement pressure technology used in the counter-pressure cast process. The effects of the technology on eliminating cast defecats and changing the solidification process and the structure of the alloy are theoretically analysed and technically tested. When the technology adapts 0. 002-0. 003 5 MPa/s as the rate of increasing pressure and 0. 08-0.12 MPa as the crystal pressure

the finished-product-rate of castings may be arrived more than 85% and the combining mechanical properties can be advanced 9%. The result shows that the technology has a notable effect to advance the quality of castings.