Three-dimensional printing with stainless steel particles

A method of three-dimensional printing, the method comprising:

• iteratively applying individual build material layers of a particulate build material including from about 97 wt % to 99.8 wt % of stainless steel particles, wherein the stainless steel particles include:
• from about 2 wt % to about 6 wt % of nickel;
• from about 14 wt % to about 19 wt % of chromium;
• from about 0.01 wt % to about 0.07 wt % of phosphorus;
• from about 0.01 wt % to about 0.08 wt % of sulfur;
• from about 2 wt % to about 6 wt % of copper;
• and
• up to about 700 ppm of carbon;
• based on a three-dimensional object model, iteratively applying a binding agent to the 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 by:
• ramping up a temperature of the sintering oven to a densification temperature of from about 1290° C. to about 1310° C.;
• pausing the ramping up of the temperature at the densification temperature for about 4 hours to about 8 hours;
• and
• ramping up the temperature of the sintering oven after the pausing from the densification temperature to a fusing temperature of from about 1350° C. to about 1400° C. for about 10 minutes to about 6 hours to form a fused three-dimensional object,
• wherein the fused three-dimensional object has an increased surface density compared to that of another three-dimensional object formed from the particulate build material and fused in the sintering oven at a constant fusing temperature.