What are the temperature limits for silicone molds during curing and operation?

Silicone is well known for its excellent thermal stability, which makes it suitable for high-heat and cold environments. At the time of the process of curing, i.e., when the silicone sets into its final shape, the temperature depends on the type of silicone being used:

• Curing temperatures: Generally between 120°C and 200°C, depending on whether it is HTV (High-Temperature Vulcanizing) or LSR (Liquid Silicone Rubber).
• After curing, silicone is often heated again at 150°C to 230°C to make it stronger, more tear-resistant, and reduce any leftover volatile compounds. When in use, silicone can handle a wide range of temperatures:
• Continuous use: -50°C to 230°C
• Short-term exposure: Up to 260°C for special high-temperature grades

This wide temperature range makes silicone perfect for things like industrial ovens, car engine parts, electronics, food-grade molds, and other applications where heat resistance is important. Knowing these temperature ranges will help manufacturers avoid damage, or any deformation, or premature failure of the molds.

Which silicone grade is best for high-temperature molding applications?

Picking the right silicone grade is really important when parts have to deal with high heat. HTV (High-Temperature Vulcanizing) silicone handles heat well and stays strong, so it’s often used in cars, planes, and industrial equipment. LSR is the best choice for making detailed parts in large quantities and stays flexible even when hot. For challenging situations that involve fuels, oils, or chemicals, Fluorosilicone or FVMQ is the best choice because it resists both heat and chemicals. Overall, for long-term high-heat use, HTV silicone is usually the most reliable and trusted option.

Checking a silicone material’s data sheet helps you understand how it will behave in real use.

• Tensile strength of the material is about the strength of the material, and what is its stretch resistance.
• Elongation at break: data to know about how far the silicone material can stretch before it loses its flexibility and breaks.
• Tear strength is key to keeping thin or delicate parts from ripping.
• Compression set data shows whether the material keeps its shape or gets deformed after being pressed.
• Thermal stability, chemical resistance, and viscosity affect performance under heat, cold, oils, or cleaners.