SME
Manufacturing Processes
Additive manufacturing
Use this for “A 30 mm part in 0.1 mm layers, 400 mm² a layer, hatch 0.1 mm at 1000 mm/s, 8 s recoat. How long is the build?”
Diagram
n
=
H
t
=
30
mm
0.1
mm
=
300
layers.
One
layer:
A
sv
+
tᵣ
=
4
s
+
8
s
=
12
s.
T = n × tₗₐᵧₑᵣ = 1 h.
Layers enlarged.
This is an example. Type your own values to start a new problem.
n
=
H (mm)
t (mm)
tₗₐᵧₑᵣ (s)
=
A (mm²)
s (mm)
×
v (mm/s)
+
tᵣ (s)
T (h)
=
n
×
tₗₐᵧₑᵣ (s)
Formulas
n
=
H
t
300
=
30
0.1
tₗₐᵧₑᵣ
=
A
s
×
v
+
tᵣ
12
=
400
0.1 × 1,000
+
8
T
=
n
×
tₗₐᵧₑᵣ
3,600 = 300 × 12
Formulas are worked in s. The step-by-step shows the conversions.
Assumptions
•
Every layer has the same scanned area A, hatched at spacing s and scan speed v.
•
Each layer adds a recoat time tᵣ, spreading fresh powder over the bed.
•
Lengths in mm and v in mm/s give the scan time in seconds.
•
A part is built in whole layers: H is a whole number of layers t thick.
Step-by-step
WE KNOW
H = 30 mm, t = 0.1 mm, A = 400 mm², s = 0.1 mm, v = 1,000 mm/s, tᵣ = 8 s
FIND
layers (n), time per layer (tₗₐᵧₑᵣ), build time (T)
Step 1 · Find layers (n)
Use n = H ÷ t
One
layer
for
each
thickness
t
,
up
the
whole
height.
n
=
30
0.1
n
=
300
Step 2 · Find time per layer (tₗₐᵧₑᵣ)
Use tₗₐᵧₑᵣ = A ÷ (s × v) + tᵣ
The
laser
sweeps
lines
s
apart
at
speed
v
,
covering
s
×
v
of
area
each
second;
then
the
recoat.
tₗₐᵧₑᵣ
=
400
0.1 × 1,000
+
8
tₗₐᵧₑᵣ
=
400
100
+
8
tₗₐᵧₑᵣ = 4 + 8
tₗₐᵧₑᵣ = 12 s
Step 3 · Find build time (T)
Use T = n × tₗₐᵧₑᵣ
Every layer takes tₗₐᵧₑᵣ, one after another.
T
=
300
×
12
T
=
3,600
s
Step 4 · Convert the answers
Change each answer back to the unit you chose.
T = 3,600 s = 1 h (1 h = 3600 s)
Check
Put the numbers back in. Both sides should match.
300
=
30
0.1
✓
12
=
400
0.1 × 1,000
+
8
✓
3,600 = 300 × 12 ✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.
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