Question

sls: layer adhesion
use the information below to answer the question.
sls printing has excellent layer adhesion. it is a good option for prototyping and production of injection mold applications. it also has good chemical resistance.

hybrid material
sls creates parts with good tensile strength and mechanical properties. occasionally, carbon or glass fiber is introduced into the build. this can change the material properties of the item. sections of a form that contain additives become stronger in tension and weaker in compression.

porosity material
printed parts for sls are about 10% porous, which can make them brittle in some cases. however, this characteristic also means the material can absorb dye, similar to the way a sponge might absorb water. when \coloring\ a form, it is generally done during the post-processing stage.

possible failures
it is important to be aware of any issues that may occur during an sls build. a commonly known problem is called delamination. this is when there isn’t enough light or heat. delamination often occurs when the laser is underpowered, or something is obstructing the light getting to the powder bed. for instance, the mirror might be cloudy, or there might be a smudge on the lens.

which of the following is true about sls printing?

• it has great layer adhesion.
• it uses a polymer resin to create prints.
• it is the slowest 3d printing process.
• it requires a support structure.

Explanation:

• For the option "It has great layer adhesion": The text states "SLS printing has excellent layer adhesion", so this is true.
• For "It uses a polymer resin to create prints": The text doesn't mention using polymer resin for SLS (SLS typically uses powdered materials like nylon, while resin is more for SLA), so this is false.
• For "It is the slowest 3D printing process": The text has no information about SLS being the slowest 3D printing process, so we can't confirm this.
• For "It requires a support structure": The text doesn't mention SLS requiring support structures (SLS parts are supported by the unused powder, so it generally doesn't need additional support structures), so this is false.

Answer:

It has great layer adhesion.