As a material widely used in industry and manufacturing, the tensile properties of thermal fuses are an important indicator of product quality and reliability.
Preparation for thermal fuse tensile test
The preparation for thermal fuse tensile test is crucial, and it lays the foundation for the smooth progress of subsequent tests.
Test instrument preparation: The commonly used test instrument is an electronic tensile tester, which can accurately measure the force and deformation of thermal fuses during the tensile process. Before use, it is necessary to ensure that the electronic tensile tester is in good working condition, all components are operating normally, and it must be calibrated and maintained regularly to ensure the accuracy of the test results.
Test environment preparation: Environmental conditions have a significant impact on the tensile test results of thermal fuses. The test should be carried out under standard conditions, that is, the temperature is 23±2℃ and the relative humidity is 50±5% RH. Therefore, the temperature and humidity of the site test need to be adjusted to the specified range in advance and kept stable.
Sample preparation: Randomly select several samples from the thermal fuse to be tested to ensure that the samples are representative. The samples are balanced under the above standard environment for more than 24 hours to eliminate the influence of environmental factors on the performance of the samples. Then, the samples are marked and numbered, and their appearance characteristics, dimensions and other information are recorded.
Sample preparation for hot-melt tensile test
The preparation of the sample is directly related to the accuracy and repeatability of the test results.
Sample cutting: Use a special cutting tool to cut the hot-melt into a sample segment with a length of 100mm±1mm. During the cutting process, ensure that the cut is flat and smooth, and avoid burrs or bevels to avoid affecting the test results.
Sample marking: Mark the gauge length in the middle of the sample, and the gauge length is generally 50mm. You can use a fine marker to gently draw two parallel marking lines on the surface of the sample as a measurement reference during the tensile test.
Testing process of hot-melt tensile test
Clamp the sample: Clamp the two ends of the sample in the upper and lower clamps of the electronic tensile testing machine respectively. When clamping, ensure that the sample fits tightly with the clamp to avoid sliding or loosening. At the same time, it is necessary to keep the specimen axially centered to prevent uneven force on the specimen due to eccentric clamping.
Set test parameters: According to the characteristics of the thermal fuse and relevant test standards, set the test parameters of the electronic tensile tester. In general, the stretching speed is set to 50mm/min, and the test accuracy is set to ±0.5%.
Start test: Start the electronic tensile tester and start stretching the thermal fuse specimen. During the stretching process, observe the deformation of the specimen and the changes in the force value and deformation curve on the tester. At the same time, record the maximum force value of the specimen during the stretching process, the force value at break, and the elongation of the specimen at break.
Data processing and result analysis of thermal fuse tensile test
Data recording and sorting: Record the data obtained from each test in detail, including the specimen number, maximum force value, breaking force value, elongation, etc. Then, sort and summarize these data, and establish a data table for subsequent analysis and processing.
Calculate tensile strength and elongation at break: According to the recorded data, calculate the tensile strength and elongation at break of the thermal fuse according to the corresponding formula. Tensile strength refers to the maximum tensile stress that the sample bears during the stretching process, and the calculation formula is: Tensile strength = maximum force value / original cross-sectional area of the sample. Elongation at break refers to the ratio of the elongation of the sample at the time of tensile fracture to the gauge length, and the calculation formula is: Elongation at break = (elongation at break / gauge length) × 100%.
Data analysis and interpretation: Analyze the calculated tensile strength and elongation at break data to evaluate the tensile properties of the thermal fuse. By comparing with the standard performance indicators of the material or the performance indicators required by the customer, it is determined whether the thermal fuse meets the quality requirements. In addition, the test results of thermal fuses from different batches or different production processes can be compared and analyzed to find out the factors affecting their tensile properties, providing a basis for optimizing the production process and improving product quality.
Factors and precautions affecting the tensile test results of thermal fuses
Environmental factors: As mentioned above, temperature and humidity have a significant effect on the performance of thermal fuses. Too high or too low temperature will change the molecular structure and physical properties of the thermal fuse, thereby affecting its tensile strength and elongation at break. Humidity will affect the hygroscopicity and lubricity of the hot melt, and thus affect its tensile properties. Therefore, during the test, environmental conditions must be strictly controlled to ensure the accuracy and comparability of the test results.
Sample preparation factors: The dimensional accuracy of the sample, the accuracy of the gauge length, and the quality of the sample surface will affect the test results. For example, if the sample size is too small or too large, the test results may deviate from the true value; inaccurate gauge length may affect the calculation of elongation at break; scratches, pits and other defects on the sample surface may become stress concentration points, causing the sample to break prematurely at these locations.
Test operation factors: including the clamping force of the fixture, the stretching speed, etc. If the clamping force of the fixture is too large, it may damage the surface of the sample and affect the force performance of the sample; if the clamping force is too small, it may cause the sample to slide during the test. If the stretching speed is too fast, the inertial force of the sample will increase, thereby affecting the accuracy of the test results. Therefore, during the test, the operator must strictly follow the standards and procedures to ensure the reliability of the test results.
Instrument and equipment factors: The accuracy, calibration status and performance of the electronic tensile testing machine will affect the test results. If the accuracy of the testing machine is not high enough, it will not be possible to accurately measure the force and deformation of the specimen; an uncalibrated testing machine may produce systematic errors, resulting in inaccurate test results; poor performance of the fixture, such as unstable clamping and rough fixture surface, will also affect the force state and test results of the specimen.
Application of hot melt wire tensile testing in quality control and product development
Hot melt wire tensile testing is of great significance in industrial production.
Quality control: By regularly conducting tensile tests on the produced hot melt wires, product quality problems can be discovered in time, such as tensile properties that do not meet standard requirements due to fluctuations in raw material quality and changes in production process parameters. Once a problem is found, measures can be taken in time to adjust and improve it to ensure the stability and consistency of product quality.
Product development: In the process of developing new products for hot melt wires, tensile testing can help R&D personnel understand the tensile performance characteristics of materials under different formulas and different production process conditions, thereby guiding the material formula design and process optimization. Through continuous adjustment and improvement, high-performance thermal fuse products that meet different application requirements are developed.
In short, the thermal fuse tensile test is an important means to evaluate the quality and performance of thermal fuse products. Through strict control of the test steps and full consideration of the influencing factors, accurate and reliable test results can be obtained, providing strong support for the production, quality control and product development of thermal fuses.
Post time: May-23-2025