Strictly control the intrinsic quality of structural foam mold raw materials

Let's take a look together:

1) There is severe network carbide segregation in the injection mold material.

2) There are machining or cold deformation stresses in the injection mold.

3) Improper heat treatment of injection molds (too fast heating or cooling, improper selection of quenching cooling medium, low cooling temperature, long cooling time, etc.).

4) The injection mold has complex shapes, uneven thicknesses, sharp corners, and tapped holes, causing excessive thermal stress and tissue stress.

5) Foam injection mold quenching heating temperature is too high to produce overheating or overheating.

6) Insufficient tempering after quenching of the injection mold or lack of tempering insulation time.

7) When the injection mold is reworked and quenched and heated, quenching is performed again without intermediate annealing.

8) The heat treatment of injection molds is not suitable for the grinding process.

9) When EDM is performed after the heat treatment of the injection mold, high tensile stress and micro-cracks are present in the hardened layer.

(2) Preventive measures

1) Strictly control the intrinsic quality of structural foam molding raw materials

2) Improve the forging and spheroidizing annealing process, eliminate mesh, ribbon, chain carbides and improve the uniformity of the spheroidized structure. ,

3) After the mechanical processing or cold plastic deformation of the injection mold should be stress relief annealing (> 600 °C) and then heat quenching.

4) As for the injection molds with complex shapes, asbestos plugging screw holes should be used to pack dangerous sections and thin walls, and graded quenching or isothermal quenching should be used.

5) Annealing or high temperature tempering is required for rework or refurbishment of injection molds.

6) The injection mold should be preheated during quenching and heating, precooling measures should be taken when cooling, and the appropriate quenching medium should be selected.

7) The quenching heating temperature and time should be strictly controlled to prevent overheating and overheating of the injection mold.

8) The injection mold should be tempered immediately after quenching, and the holding time should be sufficient. The high-alloy complex mold should be tempered 2-3 times.

9) Choose the right grinding process and the appropriate grinding wheel Pudong large injection mold.

10) Improve the EDM process of injection molds and perform stress relief and tempering.

More relevant information /