Additive Manufacturing / 3D Printing Materials Additive   manufacturing,   also   known   as   3D   printing,   is   growing   at   an   amazingly   fast   rate   and   presents   exciting   new   opportunities   in   an   incredibly diverse range of applications and industries. The   porosity   of   raw   materials   significantly   influences   manufacturing   parameters:   the   size   and   volume   of   inter-particle   void   spaces,   related   to particle   size   and   shape,   determine   the   physical   packing      of   a   powder   bed   and   In   turn,   this   will   determine   manufacturing   conditions   and   effect the physical properties and appearance of finished articles. Key Points: • Characterisation of raw materials to determine manufacturing conditions • BET Surface Area is critical to raw material specifications • BET Surface Area influences the sintering process • Determination of particulate void space and particle packing • Characterisation of finished pieces for porosity • Porosity effects mechanical strength, hardness and finish quality • Introducing porosity is necessary for reducing weight • Pore size and volume is critical to matching architectures & scaffolds • Porosity is also critical to the  weight / strength balance • Assistance with data interpretation • Expansive data presentation and comparative overlay options                   A   range   of   techniques   are   available   for   the   characterisation   of   both   raw   materials   and   finished   articles   and   these   can   be   applied   to   a   very wide   range   of   materials:   including   thermo-plastics,   metals,   alloys,   glass   and   biomedical   materials.   BET   Surface   Area   can   be   applied   to   the determination   of   printing   conditions   as   it   influences   particle   sintering.   Many   materials   used   in   additive   manufacturing   are   of   low   surface area,   such   as   thermoplastics   and   metal   powders,   and   at   MCA   Services   we   offer   BET   Surface   area   determination   by   krypton   adsorption   which is particularly suited to these materials.                   Mercury   porosimetry   is   used   for   the   determination   of   pore   volume,   pore   size   distribution   and   volume   porosity   over   a   wide   range   of   pore sizes.   For   raw   materials   this   can   be   applied   to   the   characterisation   of   inter-particle   void   spaces,   related   to   particle   packing,   and   provides complimentary   information   to   particle   size   and   shape   analysis.   Mercury   porosimetry   can   also   be   applied   to   finished   articles   and   becomes important   since   porosity   effects   physical   properties:   such   as   mechanical   strength,   hardness   and   the   anesthetic   quality   of   the   surface   finish. In   some   applications,   for   example   bio-medical,   it   is   critical   to   match   the   porous   nature   of      the   manufactured   article   with   the   existing   support material.   Mercury   porosimetry   is   particularly   useful   as   it   provides   a   full   characterisation   of   pore   volume   and   pore   size   distribution   as   well   as the measurement of volume porosity.                       MCA   Services   also   offers   the   measurement   of   bulk   density,   absolute   density   and   skeletal   density   via   our   mercury   pycnometry   and   helium pycnometry   options.   The   density   of   both   raw   materials   and   finished   articles   is   often   part   of   the   specification   parameters   and   combination   of bulk   and   skeletal   densities   can   be   applied   to   the   determination   of   Total   Pore   Volume.   Deviation   from   theoretical   density   can   be   applied   to the determination of blind pore  Key Techniques • Analysis of powders, granules and finished pieces • BET Surface Area - including krypton adsorption for low area materials • Mercury Porosimetry - pore size, pore volume & pore area distribution • Mercury Porosimetry - characterisation of particle packing / void space • Permeability and Tortuosity measurement via Mercury Porosimetry • Gas Adsorption - pore size, area  & volume distribution of mesopores • Density measurement - absolute density, bulk density & skeletal density • Measurement of Total Pore Volume