Contents
What is hatch in 3D printing?
The line-based halftoning principle called ‘hatching’ is applied to the line pat- terns naturally occuring in FDM prints, which are built up in a layer-by-layer fashion. The ability to apply color to 3D printed parts is relevant for both prototyping and manufacturing.
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.
What are the process parameters in laser coating based 3D printing techniques?
These factors can be in general divided in three main categories: laser-related factors (wavelength, power, scanning speed, hatch distance, scan pattern, beam diameter, etc.), powder- and material-related factors (flowability, size distribution, shape, powder deposition, thickness of deposited layers, etc.), and other …
Which metals can be used with selective laser melting?
Selective laser melting (SLM) machines can operate with a work space up to 1 m (39.37 in) in X, Y and Z. Some of the materials being used in this process can include Ni based super alloys, copper, aluminium, stainless steel, tool steel, cobalt chrome, titanium and tungsten.
What is a hatch distance?
Scan spacing is the separation between two consecutive laser beams. It is also called hatch spacing or hatch distance (15). As shown in Figure 11, it is measured by a distance from the center of one beam to the center of the next beam. Scan spacing is directly proportional to the production speed.
Which of the following types of material does the material jetting technology use?
What Is It? Material jetting (MJ) is one of the fastest and most accurate 3D printing technologies. It builds parts using liquid photopolymer droplets, which are cured (made solid) with UV light. Because the photopolymer resin is sprayed in droplets before it’s solidified, MJ is often compared to the 2D inkjet process.
How do you calculate scan speed?
Acquisition speed is calculated by multiplying two values: frequency (number of laser lines recorded per second) and the number of points on each laser line. Thus, a scanner with 1000 points per line with a frequency of 150Hz delivers an acquisition speed of 150.000 points per second.
What is the meaning of process parameters?
A process variable, process value or process parameter is the current measured value of a particular part of a process which is being monitored or controlled. The current temperature is called the process variable, while the desired temperature is known as the set-point.
Can lasers melt metal?
Direct metal laser melting (DMLM) is an additive manufacturing process that uses lasers to melt ultra-thin layers of metal powder to build a three-dimensional object. Objects are built from an . stl file generated from CAD (computer-aided design) data. Those .
What is hatch in laser?
Laser-assisted hatching is a scientific IVF technique that can make it easier for the embryo to “hatch” or breakthrough its outer layer or “shell” (a membrane also known as the zona pellucida) by creating an opening.
What material is jetted out in material jetting?
In material jetting, a printhead (similar to the printheads used for standard inkjet printing) dispenses droplets of a photosensitive material that solidifies under ultraviolet (UV) light, building a part layer-by-layer. The materials used in MJ are thermoset photopolymers (acrylics) that come in a liquid form.
How does the hatch distance and scan distance work?
The stripe pattern is a band defined by the scan vector width (ie stripe width), the hatching space between adjacent tracks and the scan direction as well as the overlap with the neighbouring stripes The computer controlled laser scans the surface of the bed to selectively melt the current two-dimensional slice of the CAD file.
How to set spacing between lines in hatch pattern?
Use the Spacing options on the Edit Hatch Pattern dialog to specify the distance between lines in a hatch pattern: Spacing 1 — Enter the spacing between the lines in the selected hatch pattern. Spacing 2 — If you are using two line styles, Spacing 1 defines the distance between lines of the same style.
How is the hatch distance defined in SLM?
Hatch distance. The stripe pattern is a band defined by the scan vector width (ie stripe width), the hatching space between adjacent tracks and the scan direction as well as the overlap with the neighbouring stripes. Source. Scanning patterns in SLM.
How is the hatch distance of a laser determined?
Considering Eq. (7.1) in combination with Fig. 7.7 (b), it can be observed that, depending on the diameter of the laser beam and the hatch distance, there is an overlap of the single scan paths of the moving heat source (laser spot), and therefore some points get exposed multiple times.