Rapid prototyping (RP)
Any process used to quickly develop and manufacture prototypes; 3D printing/AM is considered an RP process.
In 3D metal-printing machines using the powder bed fusion and binder jet processes, the recoater blade is a horizontal bar that spreads and smooths the powder in uniformly flat layers prior to each melt-and-solidify iteration.
The stress that remains in a part, in the absence of any external force. Residual stresses in 3D printed parts, which can cause distortion, result from uneven solidification, thermal gradients and chemical reactions during the build process.