The main factors for estimating equivalency include chemical composition, manufacturing method, finishing method, product shape, mechanical and physical properties. Additional factors such as deoxidation method, hardenability, corrosion and heat resistance and other properties may also have significant influence on steel equivalency and potential interchangeability.
Steel equivalents from around the world are usually grouped on the basis of chemical composition and, to some extent, mechanical properties. Cross-reference tables of equivalent steels often come from recommendations of standards development organizations (SDOs); recommendations from SDOs are the primary source for cross-reference tables of equivalent steels in KEY to METALS as well.
However, even when coming from SDO recommendations, equivalent steels may not have precisely the same chemistry or precisely the same tensile and yield strength and physical properties, which means that they are not absolutely equivalent and need careful consideration as to whether it can be substituted one-for-one.
It is important to recognize that a judgment on the equivalency of two steels is a very delicate and possibly error-prone process, highly dependent on circumstances in each particular case, such as heat treatment, state of delivery, service conditions etc. Also, as you see from above, the number of possible criteria for comparison and the associated combinations are very high. Consequently, defining steel equivalents requires a careful study of the specifications by qualified professionals. Most of the specifications are complex documents that cannot be condensed into a few lines of text.
With these constraints in mind, it is clear that the search and evaluation of cross-reference equivalency for a given material is enhanced by having as much relevant data readily available in a searchable and relational database. The KEY to METALS database provides the most comprehensive set of tools, algorithms and raw data to support the search process.
The KEY to METALS approach for presenting cross-reference and material equivalency candidates can be viewed as a continuum of categories that moves from the straight forward “Identical” to the more ambiguous but often insightful “Smart Cross”. Review the sidebar to learn more about the methodology for identifying and displaying cross-reference results.