multi station multi axis hybrid layered manufacturing

1. Multi-Station Multi-Axis Hybrid Layered
Manufacturing
SEMINAR
ON

2. INTRODUCTION
Additive manufacturing (AM) is a popular modern
manufacturing technology which fabricates objects from 3D
model data by layering materials.As a result of this unique
manufacturing process, it is employed to create the
component with complicated geometries by utilizing lesser
material waste and manufacturing cost.
Hybrid Layered Manufacturing (HLM) is the
process in which a 3D component is made by adding and
subtracting material layer by layer. HLM is basically for a
metallic component in which material is added by depositing
metal in wire form and a small amount of material is
removed by machining and thus making the system hybrid.

3. Hybrid Layered Manufacturing Technology

4. Subtractive manufacturing (SM) is the process which
involves removing or subtracting materials to produce
the end product. CNC machine system will remove
metal using drilling, milling, or turning. The process will
clear away segment by segment until the end product is
obtained.
Subtractive manufacturing

5. CAD
modelling
Preheating
Deposition
(TIG/MIG, Laser, Electron
beam)
Face milling
Inspection (Image
processing)
Hammering
Final machining
Finished
Components
Process flow for hybrid layered manufacturing

6. MSMA-HLM is a hybrid metal 3D printing process, and it
enables different levels of process hybridization and
integration of multiple technologies. The various levels of
process hybridization may comprise of optimal use of
different modes of manufacturing like
additive/subtractive, different thermal joining methods,
different kinematics like 3/5-axis, different layering
strategies.
Multi station multi axis – hybrid layered
manufacturing

7. The advantages of this system is that can be used to
build complex metallic objects that can find the
automobile, aerospace, medical, and heavy engineering
applications.
MSMA-HLM was obtained by putting two VMCs facing
each other and combining their Y axes . A slide for Y-
axis was mounted on top of it on which a trunnion table
(B & C axes) was mounted. Thus, the substrate can
have four axes (X, Y, B, and C axes).

8. The Z1 & Z2 of both VMCs move in unison to lift and
lower a long beam which is our Z-axis. This Z-axis beam
has six generic tool posts suitably spaced . This space
itself is variable as all the slides are clamped on
common rails. The tool post itself is generic with a grid
of tapped holes for accommodating any tool head. Each
tool post can be independently lowered or retracted by
activating corresponding pneumatic cylinder to avoid
possibilities of fouling.

10. A unique machine tool is developed for HLM, spacious
enough to lay down all stations in a row and the pre-
heating, cladding, and hammering tools are isolated from
the spindle not to affect its precision. It is a 5-axis system
with multiple independent tool stations called Multi-Station
Multi-Axis - Hybrid Layered Manufacturing (MSMA-HLM)
When tools like induction heater and pneumatic Hammer
are mounted on the spindle head of a precise CNC
machine, their heat and force will reduce efficiency of the
manufacturing processes

11. Different working methods of MSMA-HLM system
• Pre-heating the substrate
• Deposition using MIG, TIG and Laser
• Face milling
• Inspection
• Stress-relieving by Hammering

12. Preheating
Preventing techniques are used before welding/cladding to
reduce the distortion and stresses. Pre-heating leads to more
homogeneous heat input and reduces the residual stresses.
It involves heating the base metal, prior to welding, to a
specific desired temperature, called the pre-heat
temperature. Heating may be continued during the welding
process, but frequently the heat from welding is sufficient to
maintain the desired temperature without a continuation of
the external heat source.

13. Deposition
The deposition is carried out with a wire-based cladding
system by different energy sources. Deposition gives the
near net shape for the component, which can be realized
layer by layer. MIG deposition is the simplest, fastest, and
cheapest with good material integrity and can produce a
rough shape. The other processes for deposition are
• TIG based deposition and
• Laser based deposition

14. Machining
Face milling has been done to remove the scallops and to
ensure the desired layer thickness. Ball end milling is
needed to do the conformal milling in non-planar
deposition, whereas face milling is sufficient for the planar
deposition. This station will mainly contain a tool head
that can use for face milling after deposition with the
suitable cutter using a toolpath.

15. Face Milling :
Flattening the scallops, maintaining the precision of the
layer thickness, providing a good surface for smooth
cladding of the next layer and providing a shiny flat surface
for optical inspection.
Series of end milling :
This is to finish the near-net geometry to the final
dimensions. These tools will be stored in the ATC available
in MSMA-HLM.

16. Inspection
After deposition and face milling, defects such as porosity
may occur at unfilled area which reduces the capabilities
of the produced parts. The other commonly occurred
defects which identified are :
• Spatter and surface porosity
• Faulty area filling tool path
• Clad discontinuity by clogging the nozzle of the wire
• Surface crack because of residual stresses

17. If the defect is small enough to be filled during the
subsequent deposition, process flow will go to the next step
(i.e., hammering). Otherwise, the defective layer would be
removed completely, and re-deposition of the particular layer
takes place.
Porosity Formation of cracks

18. The inspection process is automated using Cameras and
image processing codes by the following methods :
1. After face milling the cameras take the digital images of
the parts
2. The outer boundary of the layer is obtained from CAD
data and superimposed with the images
3. The images that lies within the Ideal boundary is isolated
4. The colour image is converted to its binary form and
automatically detects the defects. The size of the defects
is measured.

19. Hammering
The inherent porosities and residual stresses in metallic
objects manufactured by AM processes are because of the
incomplete fusion between deposited layers, leading to an
anisotropic behaviour of the objects. Residual stresses are
developed due to strain incompatibility

20. Hammering is a method of cold working a surface. The
process consists of striking the surface to be cold worked
with a blunt-nosed tool. The operation may be performed
by hand with a ball-peen hammer or with variously
shaped punches or by a pneumatically operated hammer.
As a result, HLM is changed to reduce residual stresses
by relaxing or distributing them across a large region.
This modification was done by integrating a pneumatic
hammer into the system. The maximum force of the
current pneumatic hammering setup is 3kN and it can be
controlled by varying the inlet air pressure.

21. References :
• Multi axis multi station hybrid manufacturing
journal by KP Karunakaran (Sep 2022)
• Wikipedia
• Google scholars

22. Thank You