The researchers studied how using recycled stainless steel 630 in metal injection moulding affects the final parts. They compared virgin and recycled feedstock at different percentages. The density of green parts increased with more recycled material, but sintered density stayed the same. Mechanical properties and microstructure were not affected by recycled content. However, shrinkage decreased as more recycled material was used, which is important for maintaining part dimensions. Only a small amount of recycled feedstock can be added to virgin feedstock if tight tolerances are needed for parts.