Three-dimensional (3D) printing

A three-dimensional (3D) printing method, the method utilizing a controller including a non-transitory computer readable medium having stored thereon computer executable instructions to cause at least one step of the method, the method comprising:

• using a build material distributor, applying a metallic build material from a container containing a supply of the metallic build material;
• using an inkjet applicator, selectively applying a binder fluid on at least a portion of the metallic build material, the binder fluid including a liquid vehicle and polymer particles dispersed in the liquid vehicle, the polymer particles including a hydrophobic component and a hydrophilic component having a glass transition temperature (Tg) that is higher than the hydrophobic component, and each of the polymer particles containing one of:
• (i) polymerized hydrophobic monomers that form the hydrophobic component, polymerized hydrophilic monomers that form the hydrophilic component, and the hydrophilic component attached to a surface of the hydrophobic component;
• (ii) a ratio of polymerized hydrophobic monomers to polymerized hydrophilic monomers ranging from 5:95 to 30:70;
• (iii) a higher concentration of polymerized hydrophilic monomers at or near a surface of the hydrophobic component;
• and
• (iv) a core-shell structure with copolymerized hydrophobic and hydrophilic monomers at a core of the core-shell structure and a higher concentration of copolymerized hydrophilic monomers at a shell of the core-shell structure;
• repeating the applying of the metallic build material and the selectively applying of the binder fluid to create a patterned green part;
• using at least one heat source, heating the patterned green part to about a melting point of the polymer particles for a curing time period ranging from about 1 minute to about 360 minutes, thereby activating the binder fluid and creating a cured green part;
• using the at least one heat source, heating the cured green part to a thermal decomposition temperature of the polymer particles for a thermal decomposition time period ranging from about 10 minutes to about 72 hours, thereby creating an at least substantially polymer-free gray part;
• and
• using the at least one heat source, heating the at least substantially polymer-free gray part to a sintering temperature for a sintering time period ranging from about 20 minutes to about 15 hours to form a metallic part.