A Closer Look at Alloy Steel

Fastener Materials: A Closer Look at Alloy Steel

There are a lot of fastener options out there. When picking the fastener for your next project, you are going to want to consider the material it is made of. Many of our options include steel fasteners. The main options you have for steel are Low Carbon Steel, Medium Carbon Steel, Alloy Steel, Stainless Steel, or Austenitic Stainless Steel.

Carbon Steel
Low Carbon Steel, Medium Carbon Steel and Alloy Steel are all types of Carbon Steel. They are separated into these three groups because the mechanical properties of these fasteners are based on the amount of carbon in the fastener.

The vast majority of fasteners that are manufactured use carbon steel. This is because it is inexpensive, but also because it has a broad range of strength capabilities. Let’s take a closer look at one type of Carbon Steel: Alloy Steel.

Alloy Steel
Alloy steel is carbon steel that contains additives such as boron, manganese, chromium, silicon, etc. Additions of these elements improve the capacity of alloys to be heat treated to a wide range of strength and ductility combinations. However, the higher the strength the great the risk of hydrogen embrittlement if plated.

Alloy steels have a tensile strength in excess of 150,000 psi (1034 MPa).

SAE Grade 8 (metric class 10.9, 12.9) fasteners are made from alloy steel with AISI grades 4137, 4140, 4340, and 5140 falling into this category.

Still have some questions about fastener materials? Contact us at ProvenProductivity@bossard.com if you have questions. We are here to make sure your projects go smoothly!