This mechanical test is for the evaluation and contol of the potential for steel to become embrittled from sources of hydrogen during the plating process or from other service environments that may be exposed to the material. Primarily used as a process control test, prepared specimens are typically loaded to 75% of the material's
fracture stress value for a specified period of time without failue (24 and 200 hour tests are common, dependent on specimen types). Tests for embrittlement during the plating process typically use four specimens loaded in series. If none of the specimens fail within the specified time period, the plating process is generally considered acceptable. If one specimen fails, testing specifications allow for continuation of the test on the remaining three specimens, but with requirements to increase the load up to 90% of the material's rated fracture stress.
Our Creep/Stress Rupture equipment can be used for testing applications ranging from 12,000 - 20,000 lb. The design of the lever arm machines provide an economical method of maintaining constant tensile loads for evaluation of time-dependent material property, such as Hydrogen Embrittlement (ASTM F519). The appropriate machine capacity is dependent upon the specimen type used.
We suggest using a room temperature 12,000 - 20,000 lb Model C Creep machine. The typical load train includes two pull rods and five couplings, which allows four threaded specimens to be connected in series on each load frame. These ambient temperature machines are provided with an auto-unload feature that allows the operator to pre-set a load time period. Once this time period elapses, the force being applied to the specimen will automatically unload, ending the required load time period.