The grading scale is straightforward:
| Level | Description | Typical Disposition | |-------|-------------|----------------------| | | Very fine, widely scattered pores – barely detectable under standard viewing conditions. | Always acceptable for most applications. | | Level 2 | Small pores, still scattered but more frequent. | Acceptable for general commercial use. | | Level 3 | Moderate pore size and frequency. The "gray area" – often requires engineering review. | Acceptable only with reduction factors. | | Level 4 | Coarse pores, frequent clustering, measurable loss of section integrity. | Usually rejectable for structural parts. | | Level 5 | Severe porosity – gross discontinuities visible without viewers. | Unacceptable for all but the lowest-grade castings. |
: Common acceptable limits for general commercial, automotive, and industrial engineering applications.
A: No. The film reference radiographs are not intended for digital radiography. Use ASTM E2422 for aluminum castings and ASTM E2869 for magnesium castings when performing digital radiography. astm e155 porosity levels pdf repack
ASTM E155 doesn't just measure simple voids; it classifies defects into specific categories. The primary defect classifications include:
Deducted half a star because you still need a lightbox and film for true certification. But for practical, rapid, comparative porosity grading, this is the best tool available.
For specific defects like "Aluminum Foreign Material (More Dense)" at 3/4" thickness, the standard quantifies levels by area and diameter: m m squared the empty set m m squared the empty set m m squared the empty set m m squared the empty set m m squared the empty set The grading scale is straightforward: | Level |
This level of specificity removes ambiguity and ensures your supplier knows exactly what is being required.
: Level 1 represents the smallest/least amount of porosity, while Level 8 represents the most severe. Grading Categories : Porosity is usually categorized into:
ASTM E155 remains the standard for validating the porosity of aluminum and magnesium castings. Finding a proper can aid in training and immediate assessment. Always ensure you are using the most current revision of the standard, such as the 2020 version, to guarantee compliance and structural integrity. | Acceptable for general commercial use
Similar to gas porosity but generally larger; these appear as smooth-edged dark spots.
Some NDT training schools offer study guides that include extracted, annotated versions of ASTM E155 porosity levels for educational purposes. These are not full standards but can serve as a quick-reference repack.
