There is a certain relationship between the hardness and tensile strength of liquid silicone, but it is not a simple linear relationship. The following is a detailed explanation of this relationship:
1. Definition and influence of hardness
The hardness of liquid silicone is usually measured by a Shore durometer, ranging from 0 to 80 degrees. Hardness reflects the ability of silicone to resist external objects pressing into its surface and is an important physical property of silicone materials.
2. Definition and importance of tensile strength
Tensile strength, also known as tensile strength or strength limit, refers to the stress (σ) obtained by dividing the maximum force (Fb) that a silicone specimen withstands when it breaks in a tensile test by the original cross-sectional area (So) of the specimen, in units of MPa. It indicates the ability of silicone to resist tensile fracture and is one of the important indicators for evaluating the mechanical properties of silicone materials.
3. Relationship between hardness and tensile strength
Trend relationship:
Generally speaking, as the hardness increases, the tensile strength of liquid silicone will also increase accordingly. This is because the interaction between the molecular chains of silicone with higher hardness is stronger, allowing the material to better maintain the stability of shape and structure when subjected to tensile force.
Non-linear relationship:
Despite the above trend, the relationship between hardness and tensile strength is not a strictly linear relationship. This is because the tensile strength of liquid silicone is also affected by many other factors, such as the type of silicone, formula, production process and test conditions.
Special hardness range:
In the commonly used liquid silicone hardness range (such as 30 to 50 degrees), silicone has good operability, good physical properties after curing, and various performance indicators including tensile strength are relatively ideal.
4. Other influencing factors
In addition to hardness, the tensile strength of liquid silicone is also affected by the following factors:
Type of silicone: Different types of liquid silicone have differences in tensile strength. For example, some specially formulated liquid silicone may have higher tensile strength.
Formula ingredients: The type and amount of ingredients such as fillers, vulcanizers, plasticizers, etc. in the formula will affect the tensile strength of silicone. Reasonable formula design can improve the tensile strength of silicone.
Production process: Process steps such as molding, vulcanization, and demolding will affect the tensile strength of silicone. Appropriate production processes can ensure that silicone has the best physical properties.
Test conditions: Different test methods and standards may lead to differences in test results. In addition, the tensile strength of silicone may also change when tested in high or low temperature environments.
In summary, there is a certain relationship between the hardness and tensile strength of liquid silicone, but it is not a simple linear relationship. In practical applications, it is necessary to select the appropriate silicone hardness and tensile strength according to the specific usage scenarios and needs. At the same time, it is also necessary to pay attention to other factors that affect the tensile strength of silicone to ensure that the selected silicone material can meet the use requirements.