| Abstrakt: |
The paper addresses the issues of advanced use of pressure to promote product differentiation of alloys and increase the competitiveness of castings, approximating their properties to those of strained structure. In particular, the effect of pressure on shrinkage compensation is considered. Research has shown that when applying pressure of ∼400 MPa for 8 seconds to the liquid metal (alloy B95, dimensions Ø80x70 mm), superheated above the liquidus point by 150...200K, the volume of metal decreases by 12%. Within the next 50...60 s the volume decreases by another 1.0. 1.5%. We assume that this occurs during the transformation of the metal to a crystalline state. In the process of pressure testing a specific property of liquid metal is evident - its compressibility, which depends not only on the composition of the alloy but also on the rate of cooling, pressure quantity, and pressurization speed. During the experiments, it was found, pressure testing aimed for compression, the convergence of atoms of liquid metal, requires tooling, equipment, control system, and fulfillment of conditions at the design stages of the technological process. [ABSTRACT FROM AUTHOR] |
