EFFECT OF UNCERTAINTY PARAMETERS ON THE PART QUALITY IN A DEEP DRAWING PROCESS FOR A LOW CARBON STEEL SHEET

Reliability and robustness of deep drawing process depend on uncertainty of material properties and lubrication conditions. Practically, there are no principles or guidelines to know how much variance of factor should be controlled to increase the productivity and decrease waste. This Research presents the effect of uncertainty from material properties and friction coefficient on the thinning of round cup by Finite Element Method (FEM). The material properties are consisted of the strength coefficient (K), strain hardening exponent (n), and normal anisotropy (rm). The friction coefficient (µs) of the deep drawing process is composed of 3 pairs; punch/blank (µs(P/B)), die/blank (µs(D/B)) and binder/blank (µs(B/B)) interface. Simulationoptimization Technique is used by Response Surface Method (RSM) to create Surrogate Model to combine the objective function with Monte Carlo Simulation (MCS) to simulate the distribution according to the occurred variance of each factor. The results, it was demonstrated that DR is important to deep drawing process highly. Moreover, the variance control of friction coefficients for 3 interfaces properly (1%- 5%) can increase the variance of material properties that affects the cost. So the manufacturers should control the lubrication condition in the proper range to achieve the target efficiency and sustainably.