Vacuum casting (Vaccum Casting), also known as vacuum complex. The castable is degassed, stirred, preheated, and molded under vacuum conditions, and the secondary curing molding process is carried out for 2-3 hours in a constant temperature oven at 60°C-80°C. It is suitable for small batch trial production in the process of product development, trial production samples with complex structure, uniform wall thickness and certain functional requirements.

technical parameter:

Applicable molds: Silicone molds (lifetime 10-20 pieces).

Casting material: Two-component polyurethane PU. Materials currently used: AXSON polyurethane resin, Hei-cast polyurethane resin.

Physical properties: similar to ABS, PP-like, nylon-like, PMMA/PC-like transparent parts, soft rubber parts (40-90shord D), high temperature resistant parts (150℃), fireproof materials, etc.

General working time: 1-4 hours/piece.

Standard copy accuracy: ±0.20mm/100mm.

Thickness of casting sample: minimum 0.5mm, best 1.5mm-5mm.

The largest casting workpiece: 2000mmX1200mmX1000mm.

crafting process:

(1) Preheat the silicone mold. Heat the silicone mold to 60-70℃ in advance. If the mold temperature is too low, it will cause incomplete curing and poor physical properties. The mold temperature has a direct relationship with the dimensional accuracy of the trial product.

(2) The castable is pre-defoamed. The two liquids A and B were subjected to vacuum defoaming treatment in a vacuum box for more than 30 minutes.

(3) Pouring. Place the containers containing liquid A and liquid B in the work room respectively. After the working room is evacuated, stir liquid B from time to time to make it defoamed for 5-10 minutes, pour liquid A into liquid B, stir for 30-40 minutes, and quickly pour it into the silicone rubber mold. And return to atmospheric pressure within 1 minute to 1 minute and 30 seconds from the start of mixing.

(4) Curing. After curing for 30-60 minutes in an incubator at 60-70°C, it can be demolded. If necessary, carry out secondary curing for 2-3 hours in an incubator at 70-80°C.