In conclusion we wish to highlight what these results might mean for the cold finishing industry and the cold heading industry. Cold finishing industry: The high-temperature uniformity at the end of the soaking zone (usually <3 deg C) will positively affect the product in terms of low mechanical property variability and a high spheroidisation rate. The metallurgical results are consistent with standard requirements in terms of zero free ferrite, and below what is required for partial decarburisation depth. This results in high product quality and high production efficiency with no product rejection. It is possible to shorten the cycle in a certain time range and still maintain product quality. This represents a great benefit to the cold finishing processor because the product can be heat treated at lower energy costs for the entire cycle and at a higher production rate. This promises the heat treater a higher profit margin; or, the product can be offered at a lower price. Continuous roller hearth and batch type furnaces operating hi an endothermic gas atmosphere present no differences in terms of quality. Cold heading industry: The wire and rod quality is the most important issue. Since our results are in accordance with the standard requirements (maximum hardness, tensile strength, decarburisation, and spheroidisation), variable parameters govern wire and rod formability in the production of fasteners. Low variability of spheroidised wire and rod allow for high quality and homogeneous fastener products, easier set-up of machining equipment for cold heading, and longer tool life.
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