what is BRIGHT Steel What is difference between Bright and Black (Ms) Steel

What Is Bright Steel

Bright steel is usually a carbon steel alloy which has had the surface condition improved by drawing, peeling or grinding over the hot rolled finish supplied by the steel mill.

Bright steel is essentially black steel material that has had further processing. The bright steel is processed further in cold reduction mills, where the material is cooled (at room temperature) followed by annealing and/or tempers rolling. This process will make steel with closer dimensional tolerances and a wider range of surface finishes. The term bright drawn is mistakenly used on all products, when actually the product name refers to the rolling of flat rolled sheet and coil products.

When referring to bright steels bar products, the term used is “cold finishing”, which usually consists of cold drawing and/or turning, grinding and polishing. This process results in higher yield points and has four main advantages

• Cold drawing increases the yield and tensile strengths, often eliminating further costly thermal treatments.
• Turning gets rid of surface imperfections for bright steels material.
• Grinding narrows the original size tolerance range.
• Polishing improves surface finish.
• All cold products provide a superior surface finish, and are superior in tolerance, concentricity, and straightness when compared to black steel.

Cold finished bright steel bars are typically harder to work with than black steel due to the increased carbon content. However, this cannot be said about bright drawn sheet and black steel sheet. With these two products, the bright drawn product has low carbon content and it is typically annealed, making it softer than black steel sheet.

Uses: Any project where tolerances, surface condition, concentricity, and straightness are the major factors.

DIFFERENCE BETWEEN MILD AND BRIGHT STEEL

BLACK (MS) STEEL BARS Black Steel Bars are produced in a rolling mill by heating raw material such as billet, blooms, etc at a temperature around 1200 C through a number of rolls to achieve the desired shape and size. Some of the shapes are rounds, hexagons, flats, bars, etc. Due to the nature of the process and temperatures involved, precise control of tolerances that can be achieved in bright bars cannot be achieved in black steel bars. Therefore they are further processed to make steel bright bars for processes that require more precise accuracies. Therefore black steel bars are less expensive than bright bars.

BRIGHT STEEL BARS Bright Steel Bars are produced from black bars by passing through dies in a cold condition or by turning the bars in a peeling machine and some other processes. They are used where specific tolerance are required such as for use in CNC machines, etc. Some times heat treatment such as annealing is done before cold finishing. There are five main type of different processes to achieve the desired sizes. ·         DRAWING The black steel bars are drawn through dies of the required shape. The raw material is chosen depending on the shape to be drawn. This increases the yield strength and tensile strength. This also eliminates a number of surface imperfections caused due to the rolling process. ·         PEELING The black bars are turned to the desired sizes. This process eliminates all surface imperfections. But internal imperfections if any are exposed. This process does not increase the tensile strength of the bars ·         GRINDING The grinding process is used to narrow the tolerances and improve the surface finishes of the above two processes ·         POLISHING The polishing process improves the surface finish of the bars ·         COLD ROLLING Cold Rolling is typically used to produce complex shapes.