WHAT IS THE KEY DIFFERENCE BETWEEN A BLACK BAR & A BRIGHT BAR?
There are a variety of raw tools that are formed by steel alloys and used to design a myriad of machining components for almost all industries. Bars, wires, and rods are the three primary raw materials used for making parts such as valves, fasteners, mechanical tools, studs, bolts, pins, hinges, handles, Surgical & Medical equipment, etc.
Stainless steel bars are widely used in industries due to their increased strength and formability. These steel bars are primarily produced and used in two forms, i.e. stainless steel bright bars and stainless steel black bars.
A lot of people ask questions about the differences between the two. Well, to answer those questions, we can say that, there are some fundamental differences related to the ways these metals are processed at the mill. But, if we talk about product specification or grade of these metals, there is not much of a difference. They can be formed to serve particular objectives with varying strength, formability, and other characteristics.
Let’s try and understand the key differences between bright bars and black bars to help you decide which one would be the best for your business.
Black bars are formed by ‘rolling process’ where the steel is passed through several rolls while heating raw materials such as billet, blooms, etc. at a temperature of around 1200 C (approx. 2100 F) which exceeds steel’s recrystallization temperature. At this range of temperature, steel can be easily formed into any desired shape and can be made in much larger sizes. Forming black bars doesn’t involve second reheating passes for accuracy, and hence, they are mostly developed without any delays in the process. This procedure doesn’t allow precise control on the size and shape of the bar as it slightly shrinks after cooling. This factor is also the reason why black bars are much cheaper than bright bars.
Black steel is used in situations where precise shapes and tolerances are not required, such as in the welding and construction trades to make railroad tracks and I-beams.
To put it simply, a bright bar is an advanced processed version of a black bar. Bright bars are formed with ‘drawing process’ in cold-reduction mills where it is cooled at room temperature and further processed with annealing, turning, grinding, polishing and temper rolling. This process allows precise control over the bar’s shape and size without compromising its properties. Hence, it helps the final steel product achieve closer dimensional tolerances with a variety of surface finishes. Cold drawn bright bars provide a superior surface finishing, along with a higher degree of susceptibility, concentricity, and straightness.
As compared to black bars, bright bars are harder to work with and are also comparatively higher in cost.
However, projects where tolerances, surface condition, concentricity, and straightness are the top priorities, bright bars are the way to go.
Regardless of which industry you belong to, if you’re looking for the best stainless steel bar manufacturers and suppliers who can provide high-quality bright bars in India or abroad, Venus Wires is here to help you. Exporting a variety of stainless steel products to several European, North American, and Asian countries, Venus is the most-trusted bright steel round bar supplier in India. Visit our website to learn more about the wide range of products.