Silicone soft molds are versatile tools used in prototype production, crafts, e fabricação industrial, valued for their flexibility, detail-retaining ability, and compatibility with various casting materials (Por exemplo, resina, poliuretano). No entanto, choosing the right type and mastering curing processes are critical to avoiding defects like incomplete hardening or low durability. This article breaks down silicone soft mold types, curing technologies, principais fatores de influência, and practical applications—with clear comparisons and tips to help you optimize mold performance.
1. Types of Silicone Soft Molds: Match to Your Needs
Silicone soft molds are categorized by curing temperature and functional requirements. Each type has unique traits suited to specific scenarios.
| Tipo de molde | Curing Temperature Range | Características do núcleo | Aplicações ideais |
| Cura à temperatura ambiente (Rtv) | 20°C–25°C | – No heating equipment needed; simple to operate.- Longer curing time (12–24 horas, varies by thickness/humidity).- Gentle on temperature-sensitive materials (Por exemplo, wax, certain plastics). | Small-batch crafts (jewelry wax models), small prototype replication (Por exemplo, TV remote button panels), instructional demonstrations, and low-volume art pieces. |
| Heating-Curing (Htv) | 60°C–120°C | – Heating accelerates curing (1–3 horas), shortening production cycles.- Enhances physical properties: dureza mais alta, better abrasion/tear resistance.- Requires thermostatic ovens or heating tools. | Industrial-grade production (peças automotivas, electronic device shells like TV back covers), high-frequency mold use (Por exemplo, 50+ Ciclos de elenco), and molds needing fast turnaround. |
| Low-Temperature Fast-Curing | 0°C–10°C (refrigeration required) | – Cures quickly in cold environments (several hours to 10+ horas).- Resists low-temperature brittleness. | Cold-region manufacturing, emergency mold repairs (Por exemplo, fixing a damaged TV prototype mold), and projects where room-temperature curing is impractical. |
| High-Temperature Resistant | 80°C–120°C (cura); 200° C - 300 ° C. (service temperature) | – Cures like standard heating-curing molds but retains performance at extreme high temperatures.- Excelente estabilidade térmica; no deformation under prolonged high heat. | Componentes aeroespaciais, Peças automotivas do motor (Por exemplo, heat-resistant gaskets), and high-temperature casting (Por exemplo, metal-alloy prototypes). |
Comparação de chave: For TV prototype production—if you need to replicate small, peças detalhadas (Por exemplo, interface panels) without damaging the master model, choose RTV. For industrial-scale TV back cover mold replication (100+ unidades), HTV is better for speed and durability.
2. Processo de cura: Step-by-Step Optimization
Proper curing operation directly impacts mold quality. Below is a linear guide to RTV and HTV curing—with critical do’s and don’ts.
2.1 Cura à temperatura ambiente (Rtv) Processo
- Preparação: Ensure the work area is dry and ventilated (umidade <60%)—excess moisture causes incomplete curing (mold remains sticky).
- Mistura: Stir silicone base and catalyst (razão 10:1, per manufacturer instructions) slowly to avoid air bubbles.
- Derramando: Pour the mixture over the master model (Por exemplo, a TV button prototype) in a thin, steady stream to minimize bubble formation.
- Cura: Let stand at 20°C–25°C for 12–24 hours. For thick molds (>5mm), extend curing time by 6–8 hours to ensure full hardening.
- Desmoldagem: Only remove the master model once the mold is fully cured—premature demolding leads to deformation (Por exemplo, a TV interface mold losing slot details).
2.2 Heating-Curing (Htv) Processo
- Preparação: Use um thermostatic oven (temperature accuracy ±2°C) to avoid local overheating.
- Mistura: Same as RTV, but use HTV-specific silicone (maior resistência ao calor).
- Derramando: Fill the mold frame and tap gently to release air bubbles.
- Staged Heating:
- Preheat at 60°C for 30 minutos (evaporates residual moisture).
- Gradually raise to target temperature (Por exemplo, 80°C for TV frame molds) and hold for 1–2 hours.
- Avoid rapid temperature spikes (causes mold cracking).
- Resfriamento & Desmoldagem: Let the mold cool to 40°C–50°C before demolding—cold molds are brittle and prone to breakage.
3. Factors Affecting Silicone Soft Mold Curing
Four key factors determine curing quality—ignoring them can lead to weak molds or production delays.
| Fator | How It Impacts Curing | Practical Tips to Mitigate Risks |
| Silicone Brand/Model | Formulas vary by manufacturer (Por exemplo, Dow Corning, Wacker, local brands). RTV vs. HTV silicones have different catalyst ratios and temperature sensitivities. | – Siga sempre o manual do fabricante (Por exemplo, um silicone Wacker HTV pode exigir 90°C em vez de 60°C).- Teste primeiro uma pequena amostra se estiver usando uma nova marca. |
| Tamanho do molde & Grossura | Moldes mais grossos (>5milímetros) calça de armadilha, exigindo temperaturas mais altas ou tempos de cura mais longos. Pequeno, moldes finos (<2milímetros) curam mais rápido, mas são propensos a endurecer pouco. | – For thick molds (Por exemplo, um molde de base de TV de 10 mm): Aumente o tempo de cura do HTV em 30 minutos ou aumente a temperatura em 10°C.- Para moldes finos: Use uma sala com umidade controlada para o RTV para evitar uma cura irregular. |
| Aditivos Auxiliares | Catalisadores aceleram a cura (mas o excesso causa fragilidade); diluents reduce viscosity (but overuse weakens mold strength); pigments may affect curing uniformity. | – Use aditivos nas proporções recomendadas (Por exemplo, 1% catalisador para RTV).- Evite misturar vários aditivos (Por exemplo, catalisador + diluente) a menos que seja testado. |
| Condições ambientais | – Umidade (>60% para RTV): Causa viscosidade superficial.- Fluxo de ar (insuficiente para RTV): Retarda a cura.- Flutuações de temperatura (para TVH): Leva ao endurecimento desigual. | – Use desumidificadores para RTV em áreas úmidas.- Certifique-se de que os fornos HTV tenham controle de temperatura estável (variação não superior a ±2°C). |
4. Aplicações práticas: From Crafts to Industry
Os moldes macios de silicone são excelentes em cenários que exigem retenção de detalhes e flexibilidade. Abaixo estão casos de uso comuns com exemplos de produção de protótipos de TV.
4.1 Craft & Produção de pequenos lotes
- Jóias de jóias: RTV molds replicate intricate wax models (Por exemplo, gemstone settings) without damaging delicate details.
- Arte & Decoração: Low-temperature curing molds create resin sculptures with complex textures (Por exemplo, marble patterns).
4.2 Fabricação de protótipo
- TV Prototype Parts:
- RTV molds replicate small TV components (Por exemplo, remote control shells, button prototypes) with high detail accuracy (± 0,1 mm).
- HTV molds produce durable molds for TV back cover prototypes—supporting 50+ casting cycles with minimal wear.
- Eletrônica: Moldes para estojos para smartphones, laptop keyboard caps, and other small electronic parts.
4.3 Industrial Production
- Automotivo: HTV molds make rubber gaskets and plastic interior parts (Por exemplo, Componentes do painel).
- Aeroespacial: High-temperature resistant molds cast heat-resistant parts (Por exemplo, Juntas do motor) that withstand 250°C+ environments.
5. Yigu Technology’s Perspective on Silicone Soft Molds
Na tecnologia Yigu, we’ve found that 80% of silicone mold issues stem from mismatched mold types or improper curing. For TV prototype clients, we often recommend RTV for initial small-batch tests (Por exemplo, 5–10 interface panel replicas)—it’s cost-effective and gentle on 3D-printed master models. For clients scaling to 50+ TV prototype parts, we switch to HTV with staged heating (60°C preheat → 90°C cure) to boost mold durability. A recent case: a client using RTV for TV frame molds faced frequent tearing after 10 cycles—switching to HTV extended mold life to 60+ ciclos, cutting rework costs by 40%. Our key advice: Prioritize understanding your project’s volume, temperature needs, and detail requirements—this ensures you pick the right mold type and avoid unnecessary delays.
6. Perguntas frequentes: Common Questions About Silicone Soft Molds
1º trimestre: Why is my room-temperature curing silicone mold still sticky after 24 horas?
A1: This is usually caused by high humidity (>60%) or incomplete mixing (uneven catalyst distribution). Correções: Move the mold to a dry, área ventilada (Use um desumidificador) for 6–8 more hours; if mixing was the issue, re-mix a new batch with precise catalyst ratios (follow the manual).
2º trimestre: Can I use a heating-curing silicone mold for temperature-sensitive master models (Por exemplo, wax TV prototypes)?
A2: No—HTV’s curing temperature (60°C–120°C) will melt or deform wax, plástico, or other heat-sensitive materials. Use RTV instead—it cures at room temperature and won’t damage the master model.
3º trimestre: How can I extend the lifespan of my silicone soft mold?
A3: – For HTV molds: Avoid exceeding their service temperature (Por exemplo, don’t use a standard HTV mold for 200°C applications).- Clean molds with mild soap and water after each use (avoid harsh solvents that break down silicone).- Store molds in a cool, Lugar seco (Longe da luz solar direta) to prevent aging and brittleness.