Rheo squeeze casting process of aluminum alloy

This paper mainly introduces lspsf semi-solid pulping principle, process equipment and its upgraded PLC control system. The structural characteristics of semi-solid vertical squeeze casting molding machine, the unique translational pouring and injection system, the clamping system and its hydraulic and electrical control system are described. The process analysis and die design of wheel shaped squeeze casting parts were carried out, and the process flow and the scheme block diagram of rheo squeeze casting forming system experiment were established. The process flow experiment was carried out through casting aluminum alloy

(1) The lspsf semi-solid pulping process device controlled by PLC can automatically or manually adjust the rotation speed and direction of the inclined rotary tube, and real-time control the temperature of multiple temperature points.

(2) The translational pouring and injection squeeze casting forming system developed by Luo Shoujing and others adds the translational pouring and injection squeeze casting forming method, which is a supplement to the new compression methods (vertical pressure solidification method, inclined pouring and local pressure solidification method) proposed by Luo Shoujing and others.

(3) The designed special squeeze casting die is closely connected with the equipment, and the secondary cavity extrusion (forging) function can be realized through the clever connection between the punch and the clamping cylinder.

(4) The die adopts the insert structure. The convex and concave cavities of the die are checked and designed. The material of the die, the exhaust and overflow grooves are explained.

(5) The scheme of rheo squeeze casting system and the technological process of rheo squeeze casting were established, and the technological process was studied by casting aluminum alloy.

(6) The semi-solid slurry was prepared by lspsf semi-solid pulping process to obtain the microstructure of A356 aluminum alloy parts formed by rheo squeeze casting. The microstructure of solidification and crystallization under pressure is uniform, the primary α – al phase is round and fine, and uniformly distributed in the matrix, and the intermetallic compound is fine.

(7) A356 rheo squeeze casting products have good appearance accuracy, high finish and stable properties. The average tensile strength is 190.5mpa, the average elongation is 13.13%, and the maximum elongation is more than 19%. The average tensile strength is 241.99mpa, the average elongation is 14.46%, and the maximum elongation is 20.67%. The first stage of solidification occurs in the slurry accumulator and barrel, which can be regarded as equilibrium state; the second stage occurs in the mold cavity, which can be regarded as non-equilibrium state under the condition of high pressure cooling, which can be calculated by Scheil model.