Application and Selection Guide of Dynamic Fatigue Testing Machine in Fatigue Testing of Automotive Parts (2026 Edition)

In the automobile manufacturing and auto parts industry, the fatigue life of parts is directly related to vehicle safety and product reputation.As the trend of lightweighting new energy vehicles accelerates,Dynamic fatigue testing machineIt has become an indispensable core equipment for material research and development, parts verification and factory quality inspection.This article systematically introduces the application of dynamic fatigue testing machines in the field of automotive parts from the four dimensions of testing standards, sample requirements, testing methods and selection considerations, and gives selection suggestions based on the latest industry hot spots in 2026.

1. Applicable standards for fatigue testing of automobile parts

In different application scenarios, the testing standards that dynamic fatigue testing machines need to follow vary.The following are the most commonly used fatigue test standards in the fields of automobile manufacturing, auto parts, and auto parts:

2. Sample preparation requirements

1. Metal sample:Axial fatigue specimens recommend round rods with a diameter of 5-10mm, a gauge length of 5 times the diameter, and a transition arc R≥5mm.The surface needs to be polished with graded sandpaper to 800# to remove machining knife marks. The axial grinding direction should be consistent with the force direction to avoid stress concentration caused by transverse knife marks.

2. Composite material specimen:According to the new national standard requirements of GB/T 46220-2025, the width of type I delaminated fatigue specimen must be accurate to ±0.1mm, and the edges must be free of burrs and delamination.After preparation, the sample needs to be adjusted in an environment of 23℃±2℃ and 50%±5%RH for more than 24 hours.

3. Parts samples:Automotive parts (such as control arms, stabilizer bars, springs) need to be clamped as a whole, and the clamp design needs to avoid additional bending moments to ensure that the stress axis is consistent with the actual working conditions.During multi-channel testing, the phase difference of each channel needs to be calibrated synchronously.

3. Test methods and key parameters

Force Control Fatigue Test:Set the maximum force, minimum force (or stress ratio R=-1), frequency (usually 5-20Hz), and number of cycles (usually 10⁶-10⁷ times).Record the load-displacement curve in real time, automatically stop the machine when it breaks and save the data.

Strain controlled low cycle fatigue:Suitable for low-cycle fatigue verification of chassis parts, strain range 0.2%-2%, frequency 0.1-1Hz, recording hysteresis loop changes.

Key monitoring indicators:Cyclic stiffness decay rate (recorded every 1000 times), residual deformation, elastic modulus change, and damping ratio change.These indicators can better reflect the actual fatigue damage process of parts than the simple "number of fracture cycles".

4. Things to note when selecting a dynamic fatigue testing machine (2026 Procurement Decision Guide)

According to the selection guide released by the 2026 Testing Machine Network and recent hot discussions on the Douyin platform, the following core parameters need to be focused on when purchasing a dynamic fatigue testing machine:

1. Reserve 25%-50% margin for dynamic force capacity:After calculating the maximum dynamic load, a 25%-50% margin must be left for the equipment's rated force value to avoid long-term full load operation affecting the sensor life.For example, when testing parts with a maximum load of 10kN, it is recommended to choose 20kN level equipment.

2. Frequency range matching test requirements:Metal high-cycle fatigue usually requires a frequency of 10-20Hz; spring testing recommends 0.1-20Hz wide frequency adjustment; low-cycle fatigue focuses on 0.1-1Hz strain control accuracy.The hot trends in 2026 areBroadband coverage + multiple uses in one machine, users no longer purchase multiple devices for different testing needs.

3. Frame stiffness determines high-frequency stability:The high rigidity gantry frame can reduce elastic energy storage and avoid phase lag and resonance at high frequencies.When purchasing, ask the supplier to provide real shots of the power display curve at three frequency points of 5Hz/10Hz/20Hz to observe the fullness of the ellipse and the degree of waveform distortion.

4. Control system closed-loop accuracy:It has three closed-loop switching capabilities of force/displacement/strain, and the control accuracy is excellent within ±0.5%.By 2026, domestic equipment will have reached international levels in terms of control accuracy.Domestic replacementIt has become a hot spot for procurement, and the price of the same performance is only 1/3 of imported equipment.

5. Adaptability of fixture and tooling:Auto parts have different shapes, so you need to confirm whether the supplier supports customization of non-standard fixtures.Special-shaped parts such as springs, shock absorbers, stabilizer bars, etc. require special tooling. It is recommended to ask the supplier to provide similar customer cases.

Shandong Huayan Intelligent Equipment GroupAs a professional source manufacturer of mechanical testing instruments, it provides 20KN electronic servo dynamic fatigue testing machine (0.1-20Hz), which is widely used in the fields of automobile manufacturing, auto parts and auto parts testing.The equipment supports GB/T 3075, GB/T 15248, and QC/T series standards. Special tooling such as multi-station springs, shock absorbers, and stabilizer bars can be customized. 24-hour after-sales response is available. Samples are welcome for testing.