Study On Powder Injection Molding For 316L Stainless Steel And ZTA Ceramics

The injection molding for minus 38 u m 316L stainless steel and D50 0.5u m ZTA ceramics powder with paraffin being based multi-component binder system and 316L stainless steel containing Cu liquid-sintering were studied. The injection process parameters influencing on injection,debinding behavior and process influencing on defects ,sintering influencing on shrinkage ,density,mechanical properties,and stainless steel adding Cu for injection molding were examined. The experiment showed that flowing property of mixing was improved other than stability with increasing temperature and paraffin ratio in binder. The green body of high quality could be obtained at injection molding temperature from 160C to 180 C,injection molding pressure from lOOMPa to 120MPa ,keeping pressure from 40MPa to SOMPa ,mold- temperature 32C,cooled from 2 min to 4 min. The debinding defects could be caused by inappropriate debinding parameters such as temperature in creasing schedule,constant temperature time. The logarithm of weight loss was proportional to the reciprocal of sample thickness at temperature below 280C. The density,mechanical properties and shrinkage increase with increasing of sintering temperature. The addition of Cu could improve 316L stainless steel anti-erosion properties. The microstructure is less influenced by the ratio of binder.The detailed results summed up as follows,The injection molding 316L stainless steel sintered at 1200C for Ih under H2 has obtained a 92% relative density,106Mpa tensile strength and 1 grade anti-erosion,while at 1350C for Ih under vacuum has obtained a 94.7% relative density,297Mpa tensile strength. The injection molding stainless steel with 20wt%Cu sintered at 1200Cfor Ih under vacuum has obtained a 95% relative density,390Mpa tensile strength and 0 grade anti-erosion Because of the mechanism of liquid phase sintering existing. The injection molding ZTA ceramics at 1680 for 1h has obtained a 561MPa flexure strength,5.84 MPa .m1/2 fracture toughness and 98.01% relative density.