ADDITIVE MANUFACTURING WITH SEALED PORES
Inventors: Lianyi Chen, S. Mohammad H Hojjatzadeh, Qilin Guo
UW researchers have developed a new 3D printing technique for fabrication of metal foams with pore patterns. Unlike traditional manufacturing techniques used for fabrication of metal foams, this new metal foaming technique is entirely controllable, which enables printing of metal foams with uniform pore dispersion (and thereby tunable density), as well as custom pore patterns for lightweight structures reinforced at key points. This technique uses pulsed mode laser powder bed fusion additive manufacturing (Pulsed-LPBF AM) to fabricate the metal foams containing patterns of micron sized closed pores. Pulsed-LPBF AM is a technique that prints metal directly from digital models in a layer-wise manner. The underlying physical mechanism of pore formation during Pulsed-LPBF AM involves transformation of a cavity into a closed pore using two consecutive pulses. By adjusting the primary laser process parameters, different patterns of pores can be produced inside the bulk of the metal.