Strength testing of copper bushings is a key part of evaluating their ability to withstand different loading conditions and ensuring their reliability in actual operation. Common strength tests for copper bushings include the following:

1. Tensile Strength Test: Measure the maximum stress that the copper bushing material can withstand in the tensile process, to assess its tensile ability and ductility. Methods: Use a tensile testing machine to stretch a sample of copper bushing and measure its tensile strength (σb), i.e., the maximum tensile force that the material can withstand before it breaks. Data such as yield strength (σs) and elongation at break (δ) can usually be obtained for assessing the ductility and plasticity of the material.

2. Compression Strength Test: To test the bearing capacity of copper bushing when compressed and evaluate its compression resistance, especially for bearings and other copper bushing subjected to large compressive stress. Method: Apply compression force gradually by compression testing machine until the copper bushing is obviously deformed or destroyed, and record the maximum compression strength (σc).

3. Bending Strength Test: To detect the ability of copper bushing under bending load and evaluate its bending strength and toughness. Method: Using the three-point bending test, place the copper sleeve sample between two support points, apply a gradually increasing bending force in the center, and record its maximum strength (σf) before bending and fracture.

4. Shear Strength Test: Measure the ability of the copper bushing material to withstand the shear force and evaluate its resistance to damage under shear conditions. Method: Use shear testing machine to apply shear force to copper bushing, record its maximum shear stress (τ) at the time of destruction. 

5. Yield strength test: Evaluate the critical stress value of the copper bushing material that undergoes plastic deformation after being subjected to force, and determine the yield strength of the material. Methods: Combined with tensile tests, measure the yield point in the stress-strain curve, i.e., the value of the stress at which irreversible plastic deformation of the material begins to occur under smaller deformations.

6. Impact Strength Test: To evaluate the resistance of copper bushing materials to fracture when subjected to transient impact loads, especially brittleness under high stress conditions. Methods: Using Charpy impact testing machine, apply impact force, measure the absorbed energy of copper sleeve samples in the impact process, reflecting its impact toughness and impact resistance.

7. Fatigue Strength Test: Test the bearing capacity of copper bushing under long-term, cyclic stress, and evaluate its strength against fatigue damage. Method: Apply repeated cyclic stress to the copper sleeve under a certain stress amplitude, record the destruction of the copper sleeve after reaching a certain number of cycles, and determine its fatigue limit or fatigue strength.

8. Torsional Strength Test: Measure the damage resistance of the copper bushing material when subjected to torsional force, and evaluate its torsional strength. Methods: Use the torsion testing machine to apply torque to the copper bushing until the material undergoes torsional deformation or destruction, and record its maximum torsional strength.

9. Fracture Toughness Test: Evaluate the energy endured by the copper bushing material in the process of crack formation or expansion, and determine its resistance to crack expansion. Methods: Determine the fracture toughness of the material through fracture mechanics test, in particular, measure the stress intensity factor when crack expansion, used to determine its ability to resist crack expansion.

10. Compression strength test: To test the resistance of thin-walled or hollow copper bushings to compression when subjected to vertical pressure, and to assess their resistance to deformation. Method: The copper sleeve is placed between two parallel plates and pressure is gradually applied until the sleeve is flattened and deformed, and the strength of the flattened sleeve is recorded.

These strength tests can comprehensively evaluate the bearing capacity and stability of copper bushings under various stress conditions, thus ensuring the safety and durability of copper bushings in practical applications.