ISO 3887:2017 pdf free

ISO 3887:2017 pdf free.Steels一Determination of the depth of decarburization
Samples should be taken at locations that are representative of the bulk specimen. The location and number of samples taken depend on the nature of the material to be tested and are defined by agreement between the parties concerned.
Specimens for the metallographic methods or micro-indentation hardness tests or electron probe microanalysis should be cut from the bulk specimen perpendicular to the longitudinal axis of the product so that measurements are made on a transverse plane. This procedure permits the determination of the variation of decarburization around the periphery of the specimen. Unless otherwise specified, the corner parts which can generate abnormal decarburization shall not be included. For specimens up to about 2,5 cm diameter, the entire cross-section is polished and examined. For larger cross-sections,one or more specimens shall be prepared to assess variations in surface decarburization. The sampling scheme for large sections should be determined by agreement between the parties concerned.
Specimens for chemical analytical methods shall be of sufficient length so that the weight of incremental turnings is adequate for chemical analysis or the size of milled surfaces is large enough for sparking yet small enough to fit in the specimen holder.
The sample shall be examined in the as- delivered condition. Nevertheless if, by agreement between the parties concerned, a supplementary heat treatment is applied, every precaution shall be taken to prevent changes in mass percentage and/or in the distribution of carbon, e.g. a small sample, a short austenitization time, a neutral atmosphere.
The measuring method shall be agreed upon in writing by the parties concerned, unless it is defined in the product standard. In the absence of any agreement or requirement in a product standard, the metallographic method should be used.
The metallographic polishing, carried out by applying the usual methods, shall not round the edges.In order to achieve this, the sample may be mounted or held in a clamp, and the surface of the product may, if necessary, be protected by a metallic deposit obtained by electroless or electrolytic plating.Automatic/semi-automatic preparation techniques should be used, where possible.ISO 3887 pdf free download.