How to test whether liquid silicone is vulcanized?

Liquid silicone is a common rubber material that needs to be vulcanized during the production process to improve its physical properties and chemical stability. There are several methods to test whether liquid silicone is vulcanized:

1. Visual inspection: After vulcanization, the silicone surface will become smooth and flat, with no obvious fluidity. Through visual inspection, you can initially determine whether the silicone has been vulcanized.
 
2. Feel method: Vulcanized silicone feels harder and has better elasticity. Use your fingers to gently press the silicone. If you feel that the silicone rebounds quickly and there is no obvious deformation on the surface, it means the vulcanization is complete.
 
3. Tensile test method: Perform a tensile test on the silicone sample to measure its tensile strength and elongation. The tensile strength and elongation of the vulcanized silica gel will be significantly improved. Through testing, it can be judged whether the silica gel is vulcanized.
 
4. Hardness testing method: Use a hardness meter to test the hardness of the silicone. The hardness of the vulcanized silicone will increase significantly. Normally, the hardness of silicone should be between 30 and 40 Shore hardness. If the hardness is too low, it means insufficient vulcanization.
 
5. Combustion method: Conduct a combustion test on the silica gel sample to observe its combustion process and smell. There will be no obvious burning smell during the burning process of vulcanized silicone, and the residue after burning should be hard ash.