Tribological behavior of 17–4 PH stainless steel fabricated by traditional manufacturing and laser-based additive manufacturing methods

Abstract

This study investigates the wear and mechanical properties of additively manufactured (AM) 17–4 precipitation hardening (PH) stainless steel (SS) and compares to those of conventionally manufactured (CM) wrought specimens. Disk shape specimens were fabricated by either a laser beam powder bed fusion (LB-PBF) process or a conventional manufacturing method. Wear resistance of LB-PBF 17–4 PH SS specimens were compared to that of CM ones, for both dry and lubricated conditions under 10 N and 30 N applied loads. The wear rate for both LB-PBF and CM 17–4 PH SS was found to have a proportional relation with the applied load. The CM 17–4 PH SS specimens tended to have a higher wear rate than LB-PBF ones when tested dry, while the trend reversed for the lubricated condition. This is because the lubrication changed the dominant wear mechanism from adhesion to surface fatigue and abrasion. This trend was found to be similar for both AM and CM specimens. This was attributed to the low wear rate in lubricated condition, and high wear rate in dry condition, regardless of the type of specimens (i.e. LB-PBF or CM 17–4 PH SS). The results showed that AM parts have good potential to be an alternative to wrought counterparts in terms of friction and wear behavior.