Three-dimensional printing can include iteratively applying build material layers including stainless steel particles, iteratively applying a binding agent to individual build material layers to define individually patterned object layers that become adhered to one another to form a layered green body object, and sintering the layered green body object in a sintering oven. The stainless steel particles can include from about (2) wt% to about (6) wt% nickel, from about (14) wt% to about (19) wt% chromium, from about (2) wt% to about (6) wt% copper, and up to about (700) ppm carbon. Sintering can include ramping up the temperature to about (1240)° C to about (1320)° C, pausing for about (30) minutes to about (12) hours, and ramping up the temperature to about (1350)° C to about (1400)° C for (10) minutes to about (6) hours.