There is shrinkage on our Binder Jetting materials Steel / Bronze 420/BR, on average 2% - 3% and for the Stainless Steel 316, the average shrinkage is 20%.
This phenomenon takes place as follows: the object is printed with a metal-based powder, between each layer the objects are slightly cured to bind the powder. Once the printing cycle has been completed the printing block is placed in a kiln and is cured.
The parts are then taken out carefully from the printing block where all of the excess powder is removed.
For the Steel / Bronze 420/BR, the objects are loaded into a crucible for the infiltration with the Bronze material, this is where stints are added to allow the infiltration process to take place.
The stints are then removed and the objects are ready for dispatch (the Stainless Steel 316 does not undergo this stint stage, just the curing).
It is during the baking with the high temperatures that the changes in the size of an object can take place. Also if the object is cantilevered, the risk for deforming can take place during this part of the process.
For the Steel / Bronze 420/BR, the accuracy is:
Parts up to 7.62 cm (3 in): up to 2% shrinkage (On Average)
Parts more than 7.62 cm (3 in): up to 3% shrinkage (On Average)
For Stainless Steel 316, the accuracy is: 15-20% shrinkage.