Difference between AISI and ASTM standards

What is the difference between aisi and astm standards?

Today, the formation of various systems make use of components that are manufactured all over the world. Global import export for metal components has been on a steady rise. And with each passing day, manufacturers across the world offer competitive prices, lead times, and minimum order quantities as well. And since connectivity along with import & export regulations has become easier, it has become smoother to order these components from various countries or different states. This gave rise to standardizations in terms of the method of production, test methods, chemical composition as well as other parameters. This is what led to the formation of formal regulatory bodies such as ISO, American Iron and Steel Institute and American Society for Testing and Materials. These three bodies are the most trusted, and recognized organizations with regards to the production, grading, and supply of several components.

AISI or as also known in full as the American Iron and Steel Institute is one of the oldest trade associations set in the United States of America. Although the AISI dates back to as far as 1855, its present form was assumed in the year 1908. The reason for the foundation of  AISI was to cater to the iron and steel industries. Both the iron and steel industries had some requirements with regards to the information, investigation, as well as the creation of a forum where the intricacies pertaining to iron and steel could be discussed and solved. The aim of the  American Iron and Steel Institute is to influence public policy, while also educating people, and fashioning public opinion on the steel industry in order to nurture its growth. The  American Iron and Steel Institute is also involved in making the steel industry a safer and highly profitable sector.

On the other hand, the ASTM, or as known by its full name American Society for Testing and Materials was established somewhere in the late 1800s. Unlike the AISI, which only takes into account steel and iron components, the ASTM has become one of the largest standards developers across the globe. This means that the  American Society for Testing and Materials is not only involved in the standards for iron and steel but also of numerous other substances. Aside from both iron and steel components, the ASTM standards also include other components concerning several industries. From nonferrous metal products, petroleum products, fossil fuels, paints and aromatics, nuclear, electrical, and electronics, to textiles, rubber, plastics, water and environment technology, solar and geothermal energy, as well as medical services and devices.

Furthermore, the American Society for Testing and Materials is an institute that is responsible for the creation of standards for not only product development, but also the production of components including flanges, plates, pipes, tubes, rods, bars, fittings, pressure vessels, etc, using all the aforementioned ferrous and non-ferrous materials. Unlike the AISI, the ASTM also includes product services. Another point of differentiation between both these standards is that the members that belong to ASTM are standard users across more than 100 countries. The list of members also include manufacturers, the buyer as well as governments from these countries. Although the membership for the American Society for Testing and Materials is voluntary, the institute’s standards tend to be used in several US federal regulations.

There are about 6 Categories of ASTM Standards, as mentioned below -

The standard Specification is a category that defines the requirements of a product. The Standard Test Method is a category that is able to encompass how the test is performed in addition to the precision of the test results in the examinations carried out. While the standard Practice illustrates the sequence of operation, the standard Guide of the American Society for Testing and Materials will offer both information and options for products. On the other hand, the standard Classification is a category that offers the grouping of materials with similar characteristics, which are sorted out on the basis of the product, material used, system, and service or application. And lastly, the terminology Standard is a category that offers the agreement on the definition of terms.

Both institutions i.e. the AISI and ASTM are involved with market expansion as well as market development. Furthermore, both standards are also involved in the development of products that will serve the requirements of the community as a whole. Hence, both standards were created and exist to improve the lives of mankind, while also being aware of the interconnection that is present between society, the environment, as well as the economy.

AISI & American standards Stainless Steel Pipes and Tubes

USA America (USA) UK Germany Sweden
AISI ASTM BSI Werkstoff Nr. DIN 17006 SIS
304 ASTM A312 TP304





X 5 CrNi 18 10

X 5 CrNi 18 12

23 32
304L ASTM A312 TP304L 304S11 1.4306 X 2 CrNi 18 11 23 52
310 ASTM A312 TP310 310S24 1.4845 X 12 CrNi 25 21
316 ASTM A312 TP316 316S31 1.4401 X 5 CrNiMo 17 12 2 23 47
316L ASTM A312 TP316L 316S11 1.4404 X 2 CrNiMo 17 13 2 23 48
317L ASTM A312 TP317L 317S12 1.4438 X 2 CrNiMo 18 16 4 23 67
321 ASTM A312 TP321 321S31



X 6 CrNiTi 18 10

X 12 CrNiTi 18 9

23 37
347 ASTM A312 TP347 347S31 1.4550 X 6 CrNiNb 18 10 23 38

Also check