Processing alloy steel and various metals require exact processes done “by the book” so that the final result is what you are looking for. The reduction ratio simply refers to how much area compression occurs when producing a hot rolled bar. Interestingly, the reduction ratio of 12:1 was once the norm and resulted in quality applications, but that is not always the case today. In fact, reduction ratios as low as 6:1 are now considered perfectly alright for many applications, thanks in part to the improved casting practices today. Therefore, better is the casting practice, accordingly, the reduction ratios can vary. In the case of hot forged bars, the reduction ratio of 4:1 is considered as a standard and in the case of higher sizes, 3:1 is also acceptable these days.
Why Is the Reduction of an Area Important?
The reduction of an area indicates its ductility; in other words, this will tell you how well that particular material is able to withstand plastic deformation before a total fracture failure results. If you are working with a more ductile material, a much greater reduction in the area will occur, while materials that are less ductile, experience a much smaller reduction in area. In addition, the area reduction is relevant not just to metals but to other materials as well, such as polymers and many more. This fact is always taken into consideration when processing any type of metal.
What Can Affect the Reduction of Area?
Many factors can directly affect the reduction of area, including the temperature. If you increase the temperature, the reduction of area is easier achieved due to greater deformation, while with reduced temperature the deformation capacity reduces. In addition, cold working of the area will result in a reduced reduction of area. Even including impurities in the process, whether intentional or unintentional, can affect the reduction of area and in fact, this can result in changing a particular material from ductile to brittle. The role of the reduction ratio when processing various steel types is significant and must be kept in mind before the process begins.
At Kisco, we process steel with required reduction ratios combined with our advanced steel casting practices which help us achieve the superior internal quality of steel. Kisco steel’s superior internal soundness both for hot rolled or hot forged is widely accepted in the market especially for larger sizes.
This content was originally published on the Kisco Steel website.