The main laser parameters include
wavelength, power, scanning speed, hatch distance, scan pattern, vector length [12], ratio of length to width [25], scan angle [
25], beam spatial distribution [26], beam spot size [27], point overlapping [28], and continuous or pulsed laser operation.
Which process parameters are affecting the surface quality of a part made by SLS process?
Four parameters namely
surface orientation, layer thickness, part bed temperature and extrusion speed
have been selected for studying surface roughness while for studying part shrinkage, five parameters have been selected viz. part orientation, layer thickness, raster angle, part bed temperature and part length.
What is selective laser sintering process?
Selective laser sintering (SLS) is
an additive manufacturing (AM) technique that uses a laser as the power source to sinter powdered material
(typically nylon or polyamide), aiming the laser automatically at points in space defined by a 3D model, binding the material together to create a solid structure.
What are the primary process parameters that are considered for optimization The process of laser powder bed fusion?
In modern laser powder bed fusion systems, there are over 100 of such processing parameters, most commonly-considered among which include
laser power, layer thickness, laser scan velocity, distance between successive laser passes (also known as hatch distance) and scanning strategies
(laser scanning pattern on each …
What is selective laser sintering used for?
Selective laser sintering is an
additive manufacturing
(AM) technology that uses a high power laser to sinter small particles of polymer powder into a solid structure based on a 3D model. SLS 3D printing has been a popular choice for engineers and manufacturers for decades.
What are the disadvantages of laser sintering?
- Very expensive. The machines can often cost $250,000+, and the materials cost $50-60/kg. …
- Cool-down time of 50% of print time can mean up to 12 hours of waiting. This leads to longer production time.
- Parts have a grainy surface without any post-processing.
How fast is selective laser sintering?
Selective laser sintering (SLS) is an industrial 3D printing process that produces accurate – rapid prototypes and functional production parts
in as fast as 1 day
. Multiple nylon-based materials are available, which create highly durable final parts.
What is the process of sintering?
Sintering is the
process of fusing particles together into one solid mass by using a combination of pressure and heat without
melting the materials. Common particles that are sintered together include metal, ceramic, plastic, and other various materials.
What type of mesh makes the smoothest model?
- NURBS—get the smooth moves. Spline Modeling—or NURBS—generates accurate geometry with the smoothest surface. …
- Polygon Mesh—shell out a surface. Polygon Modeling creates a 3D object non-mathematically. …
- Multiple application platforms. Multiple modeling techniques.
What is laser scanning speed?
As laser scanning speed decreases from
2.5 m/s to 0.3 m/s
, i.e., the energy density increases, the melted tracks can be divided into three categories: unstable state, transition state, and stable state based on the flow behaviors of molten pool, which will be discussed in the Section 5.2.
Is SLS powder bed fusion?
Direct metal laser sintering
(DMLS) is the same as SLS
, but with the use of metals and not plastics. … The process sinters the powder, layer by layer. Selective Heat Sintering differs from other processes by way of using a heated thermal print head to fuse powder material together.
Does powder bed fusion need support structures?
Powder bed fusion of polymers
However, polymer PBF processes have a significant advantage over many other AM processes in that
they do not require support structures
, since overhangs and unconnected islands are supported by the surrounding unfused powder bed (Fig. 7.1).
Which polymer is suitable for PBF process?
Polymer PBF feedstock is generally certain types of semicrystalline polymers, with the most popular being
polyamide (nylon)
, with or without composite additions such as flame retardants and glass. Other feedstocks for polymer PBF include polypropylene, polyetheretherketone (PEEK), and polyetherketoneketone (PEKK).
Which one of the processes is not using a laser?
Which of the following processes does not use lasers? Explanation:
Laser Beam Machining
or more broadly laser material processing deals with machining and material processing like heat treatment, alloying, cladding, sheet metal bending, etc.
How much does selective laser sintering cost?
A current SLS machine is about the size of a Coke machine. It costs
about $150,000
and maybe twice as much if you get all the cool stuff needed to recycle powder and clean parts. It's meant for production environments with HVAC and the like.
What is the primary principle at work in a 3 D printer?
All 3d printer is based on the same basic principle to build up the parts:
a digital model is molding by adding a layer 3d material at a time to a whole physical 3d object
. This where the alternative term Additive Manufacturing comes from.
