The detection of silver-nickel-graphite electrical contacts is a key link to ensure their performance and quality. The following is a detailed summary of the detection methods of silver-nickel-graphite electrical contacts:

1. Component analysis
Silver content detection:
Method: An X-ray fluorescence spectrometer (XRF) or inductively coupled plasma mass spectrometer (ICP-MS) will be used to analyze the sample and quantitatively determine the silver content.
Purpose: Silver is the main conductive component of the electrical contact, and the detection of silver content directly affects the conductive properties of the material.
Nickel content detection:
Method: Also use an X-ray fluorescence spectrometer (XRF) or inductively coupled plasma mass spectrometer (ICP-MS) for determination.
Purpose: The nickel content determines the mechanical strength and wear resistance of the electrical contact.
Graphite content detection:
Method: Usually determined by thermogravimetric analysis (TGA) or chemical analysis.
Purpose: The graphite content affects the lubricity and oxidation resistance of the electrical contact and ensures the smoothness of the switch operation.
Impurity element detection:
Method: Use spectral analysis or chemical titration to detect the content of impurity elements such as oxygen, sulfur, and phosphorus.
Purpose: These impurity elements will affect the conductivity and corrosion resistance of the electrical contact.
2. Physical performance test
Density detection:
Method: Use the Archimedean method or gas-specific gravity method to measure the density of the sample.
Purpose: Evaluate the compactness and uniformity of the electrical contact. Higher density is usually associated with good mechanical properties.
Microstructure analysis:
Method: Use an optical microscope or scanning electron microscope (SEM) to observe the microstructure of the material.
Purpose: Observe the distribution inside the material to ensure the uniform distribution of silver, nickel, and graphite.
Porosity determination:
Method: Use mercury intrusion or nitrogen adsorption to measure the porosity of the material.
Purpose: Reflect the internal voids of the material. Lower porosity usually means better strength and conductivity of the material.
3. Electrical performance test
Resistivity determination:
Method: Use a special resistivity measuring instrument for testing.
Purpose: A key indicator for measuring the conductive performance of the electrical contact. Lower resistivity indicates that the material has excellent conductivity.
Electrical contact resistance detection:
Method: Measured by a special electrical contact resistance tester.
Purpose: To evaluate the conductivity of the electrical contact under working conditions, which is one of the core indicators for judging the performance of the electrical contact.
IV. Mechanical performance test
Compressive strength test:
Method: Use a compression tester to apply pressure to the sample until it breaks, and record the maximum pressure value.
Purpose: To evaluate the bearing capacity of the electrical contact under pressure, which is an important indicator to ensure its service life.
Hardness test:
Method: Measure the hardness of the sample with a Vickers hardness tester or a Brinell hardness tester.
Purpose: To measure the wear resistance and deformation resistance of the material.
Flexural strength test:
Method: A flexural tester will be used to apply a bending load on the sample and measure its flexural strength.
Purpose: To evaluate the strength and toughness of the material under a bending load.
V. Thermal performance test
Thermal conductivity determination:
Method: Use a laser flash method or a steady-state thermal conductivity meter to test the thermal conductivity of the sample.
Purpose: Reflect the ability of the material to transfer heat. Higher thermal conductivity helps the electrical contact to dissipate heat effectively in a high-temperature environment.
Thermal expansion coefficient determination:
Method: Use a thermal expansion meter to measure the expansion coefficient of the sample under temperature changes.
Purpose: To evaluate the dimensional stability of the material when the temperature changes. The lower thermal expansion coefficient helps prevent the contact from cracking or deforming.
VI. Other performance tests
Wear resistance test:
Method: Use a friction and wear tester to perform wear tests on the samples by simulating actual working conditions.
Purpose: To evaluate the wear resistance of the material.
Arc resistance test:
Method: Simulate the arc action under laboratory conditions to test the stability and ablation resistance of the sample under a high-temperature arc.
Purpose: To evaluate the stability and ablation resistance of the electrical contact under a high-temperature arc environment.
VII. Testing process
Sample preparation: Cut and process the sample according to the standard.
Instrument calibration: Ensure that the test equipment is in the best condition.
Test execution: Carry out various tests according to the plan and standards.
Data analysis: Organize and analyze the test data and write reports.
In summary, the detection methods of silver-nickel graphite electrical contacts cover multiple aspects such as composition analysis, physical property testing, electrical property testing, mechanical property testing, thermal property testing, and other performance testing. These test methods together constitute a complete system for quality detection and performance evaluation of silver-nickel graphite electrical contacts.