Use of grey relational analysis found to be convenientand easiest method to estimate the significance of theseprocess variables for multiple quality factors having differenttargeted objectives. In this study, it has been found that melttemperature and injection speed have almost equal influence,but more than that of injection temperature and pressure inachieving desired part shrinkage and higher part weight.These experiments using DMLS molds have shown that allprocess variables except injection pressure contributedsignificantly on shrinkage and weight at their highest (third)level. The optimized variables are compared with the range ofvariables suggested in processing data sheet of said polymer.Figure 5 DMLS mold surface after producing 5,000 Nylon 66 moldingsTable VII Significance of molding parametersInjection moldingAverage grey relational gradeby process parameters level(experimental layoutshown in Table II)Significanceof moldingparametersparameters Level 1 Level 2 Level 3 Max-MinInjection pressure 0.5700 0.6217 0.6367 0.0667Melt temperature 0.5611 0.4271 0.6607 0.2336Injection speed 0.4877 0.6182 0.7225 0.2348Injection time 0.5794 0.5720 0.6770 0.1050This has indicated that the optimized variables are either nearor slightly more than the corresponding upper limits.The surface characterization of DMLS mold even afterproducing 5,000 moldings did not show any visible damages,in spite of their low hardness, scratch and wear resistanceproperties. 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(2003), “Developmentand characterization of direct laser sintering Cu-basedmetal powder”, Journal of Materials Processing Technology,Vol. 140, pp. 314-7.Corresponding authorNagahanumaiah can be contacted at: naga@cmeri.res.in 注射成型模具英文文献和中文翻译(5):http://www.751com.cn/fanyi/lunwen_43984.html