What is the Shore hardness test method
The Shore hardness test method is a standardized method for evaluating the hardness of materials. It mainly uses the Shore hardness tester to measure the deformation degree or puncture resistance of materials under pressure. The following is a detailed explanation of the Shore hardness test method:
I. Definition and Overview
Definition: Shore hardness refers to the reading of the value measured by the Shore hardness tester, and its unit is "degree". The Shore hardness tester is one of the most commonly used methods for measuring the hardness of materials internationally, along with Rockwell hardness and Brinell hardness.
Scope of application: The Shore hardness test method is widely used in the hardness detection of elastomers or soft materials such as rubber, plastic, silicone, and foam materials.
II. Measurement principle
The principle of the Shore hardness test method is to determine the hardness of the material by pressing a pointer or ball of a fixed shape and size into the surface of the material to be tested, and then measuring the depth or rebound degree of the pointer or ball pressed into the surface of the material to determine the hardness of the material. Specifically, the Shore hardness tester scratches the surface of the sample under a certain pressure and keeps it for a period of time, then removes the pressure, measures the increment of the indentation depth or the rate of increase of the pit depth (i.e. the residual deformation) on the surface of the sample, and calculates the hardness value of the material according to the formula. The hardness value measured by this measurement method is independent of the load, so it can be used to control the processing quality on the production line.
3. Types of Shore Hardness Testers
Shore hardness testers are divided into two types: A and D (some say that they are divided into four types: A, B, C, and D, but types A and D are the most commonly used):
Shore A hardness tester: Suitable for softer elastic materials, such as rubber, soft plastics, foam materials, etc. Its range is 0~100HA.
Shore D hardness tester: Suitable for harder elastic materials, such as hard plastics, rigid polyurethane, etc. Its range is 0~100HD.
4. Measurement steps
Choose a hardness tester: According to the estimated hardness range of the material to be tested, select a suitable Shore hardness tester (type A or type D).
Calibrating the hardness tester: Calibrate the hardness tester before use to ensure the accuracy of the measurement results.
Measuring operation: Press the pointer or ball of the hardness tester steadily into the surface of the material to be tested, remove the pressure after keeping it for a specified time, and read and record the reading on the hardness tester.
Result processing: Determine the Shore hardness value of the material based on the reading. If necessary, the Shore hardness value can also be converted to other hardness units for comparison or analysis.
5. Notes
During the measurement process, ensure that the pointer or ball of the hardness tester is in vertical contact with the surface of the material to be tested to avoid tilting or sliding.
During the measurement, avoid applying excessive pressure on the material surface or removing the pressure too quickly to avoid affecting the accuracy of the measurement results.
The Shore hardness measurement method may have certain limitations for materials of different types and shapes, so the characteristics and application background of the material should be considered when selecting the measurement method and interpreting the measurement results.