22.473 DFM HOMEWORK SET # 3 Problem 1. An L9 orthogonal array material processing experiment was designed as follows: Level 1 Level 2 Level 3 A: Pre treatment A1 = HCL A2 = H2504 A3 = HCL B: Treating Temp. B1= 200 'B B2= 190 'B B3= 220 'B C: Treating Method C1= dip C2= spray C3 = soak D: Additive D1= alcohol D2= Ethanol D3= H20 The results were: Replication # 1 8, 12, 11, 13, 14, 9, 11, 9, 10 Replication # 2 7, 9, 12, 13, 19, 12, 8, 13, 11 Exp#. A B C D Results 8 7 12 9 11 12 NNN 13 13 14 19 12 11 8 9 13 10 11 Assume Smaller is better. 1. Perform Graphical Analysis of both Average and Variance (using S/N Variance transformation) 2. Perform ANOVA for Average only, determine which factor(s) are significant and % contribution 3. Determine the best factor settings for Average and S/N based on significance analysis > 5% contribution 4. Predict the expected value (EV) and confidence interval (CI) for average only, based on average and Variance ANOVA analysis