1 Introduction
2 Materials and methods
2.1 Sample preparation
2.2 Powder characterization
2.2.1 Particle size distribution
2.2.2 Particle morphology
2.2.3 Flowability
Hausner ratio H [-] | Flow description |
---|---|
1.00–1.11 | Excellent |
1.12–1.18 | Good |
1.19–1.25 | Fair |
1.26–1.34 | Passable |
1.35–1.45 | Poor |
1.46–1.59 | Very poor |
> 1.60 | Non-flowable |
2.3 Part production
Parameter | Value | |
---|---|---|
Laser power \(P_{L}\) | [W] | 180 |
Scan speed \(v_{s}\) | [mm/s] | 1000, 1250, 1500, 1750, 2000 |
Hatch spacing \(h_{s}\) | [\(\upmu\)m] | 75 |
Layer thickness \(t_{l}\) | [\(\upmu\)m] | 30 |
Beam diameter \(d_{spot}(1/e^2)\) | [\(\upmu\)m] | 105 |
Recoater velocity | [mm/s] | 100 |
Recoater type | – | Silicon-reinforced brush |
Scan pattern | – | 90° alternating |
Shielding gas | – | Nitrogen |
2.4 Part characterization
2.4.1 Density measurement
2.4.2 Determination of melt pool dimensions
3 Results and discussion
3.1 Particle size distribution
P10 | P20 | P28 | P29w | P38 | P47 | P59 | ||
---|---|---|---|---|---|---|---|---|
\(D_{10V}\) | \([\mu m]\) | 4.0 | 13.6 | 21.9 | 17.7 | 31.2 | 37.8 | 50.5 |
\(D_{50V}\) | \([\mu m]\) | 9.5 | 20.2 | 28.3 | 29.1 | 37.9 | 46.7 | 59.3 |
\(D_{90V}\) | \([\mu m]\) | 19.3 | 29.7 | 35.8 | 45.1 | 47.3 | 57.3 | 71.9 |
\(D_{90V} - D_{10V}\) | \([\mu m]\) | 15.2 | 16.1 | 13.8 | 27.4 | 16.1 | 19.5 | 21.4 |
3.2 Particle morphology
P10 | P20 | P28 | P29w | P38 | P47 | P59 | ||
---|---|---|---|---|---|---|---|---|
\(f_{circ}\) | [-] | \(0.95 \pm 0.07\) | \(0.90 \pm 0.09\) | \(0.90 \pm 0.10\) | \(0.92 \pm 0.09\) | \(0.89 \pm 0.11\) | \(0.84 \pm 0.14\) | \(0.88 \pm 0.11\) |
\(A_R\) | [-] | \(0.85 \pm 0.10\) | \(0.81 \pm 0.12\) | \(0.82 \pm 0.12\) | \(0.83 \pm 0.12\) | \(0.82 \pm 0.11\) | \(0.81 \pm 0.12\) | \(0.82 \pm 0.12\) |