For Dimensional Control of 316L Stainless Steel
(Neal Meyers, Don Heaney) (Nathanael Lawton)

Carbon, oxide level, oxygen species, alloy content, and furnace atmosphere oxygen level all play an important role in the sintering response of stainless steels. The current study on dimensional control of 316 stainless steels has shown these interactions to be complex. In addition, dimensional variation imparted by chemistry variations can easily be masked by other factors. This study will build from the experience from Year I on 316L stainless and apply the testing methods and models to 400 series stainless steel as well as precipitation hardening stainless steel. Methods will be developed to compensate for dimensional variations imparted by variations in powder chemistry, oxygen species, and processing binder/lubricant residues. These methods may include altering the partial pressure of oxygen or carbon potential in the furnace atmosphere and heating schedule modifications. Neural network modeling will be employed for prediction of dimensional change.
Determine the effects of chemistry variations and powder size on sintering shrinkage in 316L stainless steel. Currently, a trial-and-error approach is used in industry to determine sintering conditions with each new lot of powder. This research will formulate a predictive tool for sintering shrinkage given a chemistry and particle size.