Fracture behaviour of selective laser sintered Rapidsteel 2.0 under static and dynamic loading

Selective laser sintered Rapidsteel parts were sintered and infiltrated with Cu - 10 at.-%Sn, in two different atmospheres (e.g. 30%H-2 - 70%N-2 and vacuum with a partial pressure of 200 mbar of Ar). The processing atmosphere had a significant effect on the mechanical properties of the infiltrated parts. The part sintered/infiltrated in a 30%H-2 - 70%N-2 atmosphere, exhibited a tensile strength of 780 MPa and a ductility of 4.45%. However, the tensile strength was reduced moderately to 650 MPa while the ductility was increased significantly to 11.7% by changing the sintering/infiltration atmosphere from 30%H-2-70%N-2 to vacuum + Ar. Furthermore, the parts processed in a vacuum + Ar atmosphere exhibited a better fracture resistance than parts processed in 30%H-2-70%N-2. The improvement in ductility and fracture resistance for parts processed in vacuum+Ar atmosphere was primarily due to the elimination of nitrides. For both cases, ductile fracture occurred in stainless steel particulate and striation was found in the bronze infiltrant.