ASTM E155-20 pdf free download.Standard Reference Radiographs for Inspection of Aluminum and Magnesium Castings.
1.1 These reference radiographs illustrate the types and degrees of discontinuilies that may be found in aluminum-alloy and magnesium-alloy castings. Thc castings illustrated are in thicknesses of ¼ in. (6.35 mm) and ¾ in. (19.1 mm). The reference radiograph films are an adjunct to this document and shall be purchased separately from ASTM International if needed.
1.2 These film reference radiographs are not intended to illustrate the types and degrees of discontinuities found in aluminum-alloy and magnesium-alloy castings when performing digital radiography. If performing digital radiography of aluminum-alloy castings, refer to Digital Reference Image Standard E2422. If performing digital radiography of magnesium-alloy castings, refer to Digital Reference Image Standard l2869.
1.3 This document may be used where no other applicable document exists, for other material thicknesses for which it has been found to he applicable and for which agreement has been reached between the purchaser and the manufacturer.
1.4 From lime to lime, there may be minor changes to the process for manufacturing of the reference radiograph adjunct materials. These changes could include changes in the films or processing chemicals used, changes in the dies or printing for the cardboard mats. etc.; however, in all cases, these changes are reviewed by the Illustration Monitoring Subcommittee and all reference radiographs are reviewed against a fixed prototype image to ensure that there are no changes to the acceptance level represented by the reference radiographs. Therefore, the adjunct reference radiographs remain valid for use with this standard regardless of the date of production or the revision level of the text standard.
3. Terminology
3. 1 Definitions—Definitions of terms used in this standard may be found in Terminology E1316.
3.2 Definitions of Ternis Specific to This Standard:
3.2.1 The terms relating to discontinuities used in these reference radiographs are described based upon radiographic appearance.
3.2.2 foreign materials, li—appear as isolated. irregular, or elongated variations of film density, not corresponding to variations in thickness of material, nor to cavities.
3.2.2.1 Discussion—They may be due to the presence of sand. slag, oxide or dross, or metal of different density.
3.2.3 gas holes, nappear as round or elongated, smooth- edged dark spots. occurring individually, in clusters, or distributed throughout the casting.
3.2.4 gas porosity, n—represented by round or elongated dark spots corresponding to minute voids usually distributed through the entire casting.
3.2.5 microshrinkage (frathery type). n—microshrinkage having an elongated appearance resembling feather-like streaks.
3.2.6 inicroshrinkage (sponge type), n—microshrinkage having a spongelike appearance. and more massive and equiaxed than the feathery type.ASTM E155 pdf download.