Experimental investigation and numerical simulation of the influence of the strain rate in laser forming are presented. To isolate and effectively study the strain rate effects, which are temperature dependent, a “constant peak temperature” method is developed with the aid of numerical modeling and solution. Under the condition of the constant peak temperature, the effects of strain rate on forming efficiency, residual stress and hardness of the formed parts are studied both experimentally and numerically. In the numerical model, the temperature dependence and strain-rate dependence of the flow stress and other material properties are considered. The simulation results are consistent with the experimental observations. [S1087-1357(00)01004-2]

Issue Section:
Technical Papers
Keywords:
forming processes, laser beam applications, hardness testing, deformation, bending, finite element analysis
Topics:
Lasers, Stress, Temperature, Flow (Dynamics), Computer simulation, Deformation
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 by ASME
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