Austenitic Stainless Steels (ASS) have vast applications in automotive, marine and medical due tohigh strength and corrosion resistance. This study presents the results of corrosion behavior of powderinjection molded 316L Stainless Steel parts. A spherical shape, water atomized 316L SS powder wasused in this study. Feedstock was prepared using Z-blade type mixer and viscosity was measuredusing a capillary rheometer. A vertical injection molding machine was used for injection molding oftest samples. The binder was removed by solvent extraction and thermal debinding followed bysintering in vacuum at 1325°C for 2 hrs. Heating and cooling rate of 5-10oC/min was maintained tominimize the evaporating species, Ni, Cr during the sintering process. Sintered test samples weretested for shrinkage, hardness and tensile strength. Corrosion response was of sintered test sampleswere measured by using weight loss method in Ringer’s Solution of PH 7.4 for 15 days. Sintereddensity achieved was approximately 96%. Tensile strength of test samples with 65 V% solid loadingwas 481MPa, elongation 22% and hardness 76HRB. The test samples sintered at 10oC/min andfollowed by the cooling at the same rate showed improved corrosion resistance compare to thosesintered at low heating and cooling rate. High cooling rate reduced the evaporation of Cr anddeveloped passive chromium oxide layer on the test samples during corrosion test and resultedreduced corrosion.
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