The material testing machine is the core equipment for testing the mechanical properties of materials, such as strength, elastic modulus, ductility, etc. Its operational accuracy directly affects the accuracy of experimental results. The following provides a systematic explanation of the usage details, including equipment preparation, operation procedures, parameter control, data processing, and maintenance.

1、 Preparation before use

1. Equipment inspection

-Mechanical components: Check if fixtures, loading rods, and sensors are clean and rust free, and apply lubricating oil to moving parts such as screws and guide rails.

-Electrical system: Confirm that the power grounding is good, the emergency stop button function is normal, and the data cable connection is stable (to avoid signal interference caused by poor contact).

-Calibration status: Check the last calibration record. If it exceeds the validity period (usually 6 months), the force value, displacement, and deformation sensors need to be recalibrated.

2. Environmental preparation

-Temperature and humidity control: The laboratory temperature is maintained at 23 ± 2 ℃, with a humidity of 40% -60%, to avoid material moisture absorption or thermal expansion and contraction affecting data.

-Vibration isolation: Ensure that the testing machine is placed on a stable platform, away from large equipment such as centrifuges, to reduce vibration interference.

3. Sample preparation

-Standard size: Process the sample according to the specifications (such as smooth parallel sections and standard spacing in accordance with ISO standards for tensile samples), avoiding burrs or dimensional deviations.

-Marking and measurement: Measure the sample size (diameter, thickness) with a vernier caliper, record the original data, and mark the positioning line on the surface of the sample.

2、 Operation process and parameter settings

1. Sample clamping

-Centering adjustment: fix the sample vertically on the upper and lower clamps, and use the dial indicator or laser centering instrument to ensure that the axis coincides with the loading direction (deviation<1 °).

-Preloading: Apply 5% -10% of the test force to eliminate the mechanism gap, then reset the force value and displacement data to avoid initial looseness affecting the linear segment measurement.

2. Parameter setting

-Loading rate: Select the standard rate based on the material type (such as metal stretching 1-10mm/min, composite material 0.5-5mm/min).

-Sampling frequency: Dynamic test setting ≥ 100Hz, static test ≥ 10Hz, ensuring the capture of peak force and fracture point.

-Protection settings: Enable overload protection (such as maximum force limit of 110%) to prevent equipment damage; Set displacement limit to avoid damaging the sensor.

3. Experimental execution

-Uniform loading: After starting, observe the force displacement curve. If there is any abnormal fluctuation (such as sudden increase/decrease), immediately pause the inspection of the fixture or sample.

-Post fracture processing: After the sample fractures, save the data, slowly unload and remove the broken parts to avoid residual fragments in the fixture affecting subsequent experiments.

3、 Data recording and processing

1. Real time monitoring

-Record key parameters: tensile strength (σ _ b), yield strength (σ _ 0.2), elongation at break (A%), elastic modulus (E).

-Take a screenshot to save the force displacement curve, label the yield point, maximum force, and fracture location for subsequent analysis.

2. Data processing

-Correction calculation: Correct the original data based on the sensor calibration coefficient, for example, actual force value=collected value x calibration slope.

-Outlier removal: When the dispersion coefficient of the same batch of samples is greater than 5%, check the consistency of sample processing or testing conditions.

3. Report output

-Generate a test report containing tables, curves, and calculation processes, indicating traceability information such as testing machine model, calibration date, environmental conditions, etc.

4、 Daily maintenance and troubleshooting

1. Cleaning and maintenance

-Daily maintenance: Clean the fixture residue, cover the equipment with a dust cover to prevent dust from entering the guide rail or sensor.

-Regular lubrication: The lead screw and gear are coated with high-temperature lithium grease every month, and the fixture guide groove is cleaned and coated with anti rust oil every quarter.

2. Calibration and Verification

-Force calibration: Use standard weights (such as Level 1 accuracy) or calibrators to cover the range of 20% -100%, with an error of<± 1%.

-Displacement verification: Verify the linearity of the displacement sensor and correct system errors using a grating ruler or laser interferometer.

5、 Safety operation standards

1. Personal protection: Wear cut resistant gloves during operation (to prevent pinch injuries), and do not touch sensors or touch screens with gloves.

2. Emergency response: In case of sudden power outage, immediately cut off the power supply, restart and check the self checking status of the equipment; Activate the protective cover when the sample ruptures and splashes.

3. Prohibited behavior: Overloading, no-load operation, or direct cleaning of fixtures by hand (using specialized tools) are strictly prohibited.