Difference Between 1018 & 1215 Carbon Steel
1018 Carbon Steel vs. 1215 Carbon Steel
In the world of manufacturing and machining, there are a handful of common material grades that we see all the time. Specifically in the screw machining industry, two of the most common materials we see are 1018 and 1215 grade carbon steel. They are both very versatile materials that are readily available in multiple sizes, shapes, and forms, thus lending themselves for lots of projects. Although their chemical compositions are very similar, they are also very different. Lets take a dive in and compare these two materials to see which is best for your project.Between the two grades, 1018 carbon steel is the most popular because it is the cheapest steel on the market, in bar form. When compared to 1215, 1018 is usually 10-15% cheaper from a raw material perspective. However, it has machining limitations that can out-weigh the cost savings. This grade of material can only be machined so fast because the metal shavings that are produced during cutting are stringy and gummy (see image to the left). Not only does this mean slower cycle times, but it can also lead to large “birds’ nests” on the tool or workpiece (see image below). It also affects the tool life and cutting ability, especially when trying to achieve a desired surface finish. Both issues lower the machine uptime and efficiency, thus affecting the piece price of the part.
On the flip side, 1215 carbon steel is not as cheap as 1018 in raw material form but has a 25-40% overall cost reduction. This is due to the higher machining speeds and efficiencies gained by the addition of Sulphur and Phosphorous into the material. These elements provide faster cutting speeds and excellent chip breaking properties that minimize tooling and machine maintenance. Furthermore, 1215 material can hold tighter tolerances and allow for smoother, brighter finishes.
So, from a cost perspective, 1215 is the cheapest overall option. However, sometimes the application or function of the part being designed will dictate which material is required. If your part requires bending, welding, or case hardening processes, 1018 material is the best choice. This would lend itself great for parts likes spacers, studs, rivets, pins, and shafts. 1215 on the other hand is ideal for low stress applications like fittings, bushings, inserts, or couplings.
In summation, one cannot simply look at one factor but must consider the application of part, while also accounting for material and machining costs to come up with the best overall proposition. Both the engineers and purchasing teams need to work together to make sure all these factors are considered. This information will help them to design parts that are not only functional, but also cost effective.