Additive Technologies 2 - Material Jetting and Powder Bed Fusion

True or false?

Material jetting uses the basic principles of inkjet printing to create an object.

• TRUE

• FALSE

Which of the following methods is used to eject ink from the printhead during material jetting?

I. thermal method

II. piezoelectric method

• I only

• II only

• Neither I nor II

• Both I and II

Which of the following materials are most suitable for material jetting?

• Ceramic powders

• Liquid polymers

• Photoresist

• Metal wires

Which of the following methods can NOT be used to obtain inks for material jetting?

• Melting a solid

• Dissolving a solid in a solvent

• Condensing a gas

• Suspending solid particles in a carrier liquid

If the viscosity of the printed material is too high, it can be decreased to an acceptable point by ...

• Heating it in the printhead

• Cooling it in the printhead

• Heating it on the printbed

• Cooling it on the printbed

True or false?

Sometimes surfactants are added to material jetting inks in order to ensure printability.

• TRUE

• FALSE

When must the liquid-to solid-phase change occur during material jetting?

I. When the ink is in the printhead

II. When the ink leaves the printhead

III. Immediately after the ink hits the printbed or previous layer

• I or II

• II or III

• III only

• I, II, or III

Which of the following droplet properties do NOT affect print quality during material jetting?

• Location of droplet's arrival

• Droplet velocity

• Droplet size

• Droplet temperature

True or false?

Crowns are formed when smaller droplets break from large droplets during material jetting.

• TRUE

• FALSE

Which of the following statements best describe continuous stream material jetting?

• A steady pressure is applied to the fluid reservoir causes a pressurized column of fluid to be ejected from the nozzle, which then breaks into droplets

• Individual droplets are produced directly from pressure pulses in the nozzle

• Pressure pulses in the nozzle cause a pressurized column of fluid to be ejected from the nozzle

• There is no such thing as continuous stream material jetting