WCA May 2016

Furnaces and heat treatments

Of all the processes that benefit from the skill and experience of the wire maker, heat treatment stands out. Heating rates in actual practice routinely exceed those in controlled laboratory experiments, with changes in the material occurring at temperatures a few degrees above “ideal” transformation temperatures. In the plant, transformation changes during cooling generally occur at temperatures a few degrees below those plotted in the textbook graphs. Because the temperatures at which transformation takes place are critical to heat treatment, understanding these graduations is key to the hardness and strength of the wire that comes out of the furnace. When this knowledge is second nature to the wire maker, it is key to the quality

of the finished product that comes out of the plant. Image courtesy of QED

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Wire & Cable ASIA – May/June 2016