Metallic and Other Inorganic Coatings - Test for Residual Embrittlement in both Metallic-Coated and Uncoated Externally-Threaded Articles and Rods - Inclined Wedge Method
|Publication Date:||15 February 2000|
|ICS Code (Metallic coatings):||25.220.40|
This International Standard specifies a method of determining, on a statistical basis, the probability of the existence of hydrogen embrittlement or degradation in:
a) a batch of barrel electroplated, autocatalytic plated, phosphated or chemically processed threaded articles;
b) a batch of rack plated threaded articles or rods.
This International Standard is applicable to threaded articles and rod made from steel with an actual tensile strength ≥ 1 000 MPa (corresponding hardness values: 300 HV, 303 HB or 31 HRC) or to surface-hardened threaded articles or rods. It is not applicable to fasteners.
The test method is carried out after hydrogen embrittlement relief heat treatment and may also be used for assessing differences in processing solutions, conditions and techniques. The test method has two main functions: a) when used with a statistical sampling plan it can be used for lot acceptance or rejection; b) it can be used as a control test to determine the effectiveness of the various processing steps including pre- and post-baking treatments to reduce the mobile hydrogen in the articles or rod.
Although the test method is capable of indicating those articles that are embrittled to the extent defined in clause 2, it does not guarantee complete freedom from embrittlement.
This International Standard does not relieve the plater, processor or manufacturer from imposing and monitoring suitable process control.
NOTE 1 The use of inhibitors in acid pickling baths does not necessarily guarantee avoidance of hydrogen embrittlement.
NOTE 2 Annex A provides guidance on sources of introduction of hydrogen into threaded articles.