ASTM E1077-14 pdf free download.Standard Test Methods for Estimating the Depth of Decarburization of Steel Specimens.
1.1 These test methods cover procedures for estimating the depth of decarburization of steels irrespective of the composition, matrix microstructure, or section shape. The following basic procedures may be used:
1.1.1 Screening methods.
1.1.2 Microscopical methods.
1.1.3 Microindentation hardness methods.
1.1.4 Chemical analysis methods.
1 .2 In case of a dispute, the rigorous quantitative or lineal analysis method (see 7.3.5 and 7.3.6) shall he the referee method. These methods can he employed with any cross- sectional shape. The chemical analytical methods generally reveal a greater depth of decarburization than the microscopical methods but are limited to certain simple shapes and by availability of equipment. These techniques are generally reserved for research studies. The microindentation hardness method is suitable for accurate measurements of hardened structures with relatively homogeneous microstructures.
1.3 The values stated in SI units are to he regarded as standard. No other units of measurement are included in this standard.
6. Sampling
6.1 Samples should be taken at locations that are representative of the bulk specimen. The location and number of samples taken depends on the nature of the material to be tested and will be defIned Upon agreements between manufacturer and purchaser.
6.2 Specimens for screening tests using bulk hardness tests. such as the Rockwell test, should be small enough so that they can be properly supported on the anvil of the tester. The specimen surface should not be altered except for scale removal (if present) using a method that will not alter the subsurface metal.
6.3 Specimens for the microscopical methods or for micro- indentation hardness tests or for macroscopic screening methods 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 determination of the variation of decarburization around the periphery of the specimen.
6.3.1 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. Figs. 1-3 show examples of typical sampling schemes that may be used for larger sections; the sampling scheme for large sections should be determined upon mutual agreement between manufacturer and purchaser.
6.4 Specimens for chemical analytical methods must be of sufticient 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 lit in the specimen holder.ASTM E1077 pdf download.