Grain Coarsening Resistance of Low-Carbon Drawn Wire during the Annealing Process

摘要

Low-carbon steel wires are widely used for fasteners, such as screws, rivets, and nuts. A drawing process prior to annealing is commonly applied for accurate diameter in order to be cold headed precisely with ease. Nevertheless, the above process tends to cause abnormal grain growth if the manufacturing process of steel wire is not properly controlled. It is well known that initial grain size is a key factor to affect the nuclei of recrystallization and precipitates have the benefit to inhibit the grain growth. This research shows that finishing rolling temperature is crucial for obtaining uniform ferrite grain prior to drawing and cooling control after rolling can induce the precipitation of AIN. According to the adjusted manufacturing process of low-carbon steel wire, abnormal grain growth can be effectively prevented for the drawn wire subjected to annealing treatment.