Liquid mold silicone must undergo repeated demolding, cleaning, and reuse when reproducing complex workpieces. Whether a mold is durable depends largely on tear resistance. Silicone molds with better tear resistance are less likely to develop cracks from pulling, undercuts, or stress at detail areas during demolding, thereby extending mold service life.

Tear resistance is related to material formulation, hardness, mold structure, and demolding method. Lower-hardness silicone offers high flexibility, suitable for reproducing workpieces with rich detail and numerous undercuts, but if tear resistance is insufficient, cracks may still occur at weak points during demolding. Higher-hardness silicone provides better support, but for complex structures, it may also be damaged during demolding due to insufficient elasticity. Therefore, when selecting mold silicone, one should not only look at hardness but also pay attention to tear strength, elongation, and resilience performance.

Mold structure also affects service life. Reasonable parting surface design can reduce pulling during demolding; adequate outer mold support can prevent mold deformation during pouring; appropriate pouring gate and venting positions help reduce demolding resistance. For molds requiring multiple reproductions, it is recommended to consider the demolding path during the mold-making stage, rather than relying solely on later-stage operations to compensate for structural issues.

Demolding operations are equally important. Silicone molds have elasticity, but this does not mean they can be pulled arbitrarily. During demolding, slowly separate starting from the parting line or edge positions, avoiding forced pulling from detail areas. For workpieces with fine teeth, deep grooves, or thin-wall structures, demolding can be assisted with compressed air, soft tools, or slight twisting to reduce localized stress concentration.

To improve mold life, attention must also be paid to use and storage conditions. After each use, residual material on the surface should be cleaned off, avoiding prolonged solvent immersion. During storage, keep flat, cool, and dry, avoiding heavy pressure and direct sunlight. If the mold develops obvious hardening, cracks, or deformation, replace it promptly to avoid affecting reproduction precision.

The tear resistance of liquid mold silicone is one of the key indicators determining whether a mold can be stably reused. When selecting materials, enterprises can comprehensively evaluate based on workpiece structure, reproduction count, pouring material type, and demolding difficulty. Through reasonable material selection, optimized mold structure, and standardized demolding operations, mold service life can be effectively extended and small-batch production costs reduced.

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