ASTM F519 | Hydrogen Embrittlement Testing
ASTM F519 describes sustained load testing (SLT) of high strength steels to evaluate the possibility of hydrogen embrittlement. The test determines the effect the plating and post-plating processes have on the material’s ductility. The test is conducted by applying a long term sustained uniaxial tension. If cracks occur, an increased force is applied for the remainder of the test. Hydrogen embrittlement occurs when metals are exposed to various sources of hydrogen during the plating process or certain service environments which causes the host metal to lose ductility and become brittle. This test is used by plating and other post-processing companies to determine the effect of the process on the material.
To perform the SLT procedure, an electro-mechanical testing machine equipped with the appropriate specimen grips and software capable of maintaining a constant force are necessary. If you need to conduct Hydrogen Embrittlement tests according to ASTM F519, please read the entire specification from the relevant ASTM publication.
ASTM F519 | Hydrogen Embrittlement Testing
- The round tension bar should be prepared with the necessary notch as described in the testing standard prior to plating. Ensure that the notch is manufactured in a way where plating can be achieved at the root of the notch. ASTM F519 allows for various angles and fillets on the notch.
- Link a minimum of 4 plated samples using couplings that have a higher tensile strength than the samples. Zero the testing machine without the specimen inserted in the grips. Then, connect the chain of samples to the testing machine using the threaded bolt grips and start loading the sample.
- Using the specimens’ bare notched cross section dimension and the Notched Fracture Strength (NFS), calculate the load required to achieve 75% of the NFS.
- Conduct the test by loading the samples to the calculated value and then holding the load for the amount of time specified in ASTM F519 or until the material yields.
- If only one of the specimens fracture within the 200 hour timeframe, increase the load as specified in the testing standard and hold the new load for an additional hour.
- Classify the plating process as acceptable or embrittlement according to ASTM F519.
- Report should include information such as time under load.
- Plating processes are considering to be acceptable if one of the below requirements are achieved:
- No fracture occurs following the end of Step 4.
- No additional specimen fractures following the end of Step 5.
- If multiple specimens fracture during step 4, or an additional specimen fractures during Step 5, the plating process should be considered embrittlement and should be reevaluated to determine the cause of nonconformance.
ASTM F519 | Hydrogen Embrittlement Testing
ASTM F519 | Hydrogen Embrittlement Testing
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