Percent Cold Work
Calculate the percent cold work (area reduction), %CW = (A₀ − A_f) ÷ A₀ × 100%, from the initial cross-section area A₀ and the final area A_f after cold plastic deformation (rolling, drawing, stamping). The result, in %, shows how much the material was deformed below the recrystallization temperature. Cold work strain-hardens the metal: it raises the yield strength and hardness and lowers ductility as dislocations multiply and tangle. It is the parameter used to control properties before an anneal. Enter the initial and final areas.
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Percent cold work
Cold working a metal means deforming it plastically below its recrystallization temperature (cold rolling, wire drawing, stamping). The amount of cold work is measured by the area reduction: %CW = (A₀ − A_f) ÷ A₀ × 100%, comparing the cross section before and after deformation. The effect on properties is dramatic, and it goes by the name strain hardening (or work hardening): as the metal deforms, dislocations (line defects in the crystal lattice that allow slip) multiply and tangle, locking one another in place. The result is that the yield strength and the hardness rise while ductility falls — the material gets stronger, yet more brittle and harder to keep forming. That is why %CW works as a process control parameter: the shop decides how much to harden in order to reach the target strength, and when an intermediate anneal becomes necessary (a heat treatment that recrystallizes the metal, erasing the strain hardening) so that deformation can continue without cracking. Enter the initial and final cross-sectional areas.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.