Article continued
from page 15.
checking and wear damages during forging, the tool
was built using low-cost steel, and a high-temperature Co-based alloy was applied in the heat checking
areas. In contrast to the mechanical bonding of the
CVD/PVD/thermal spray coatings, DMD material
is metallurgically bonded to the base steel and can
withstand the thermal and fatigue loading of the
A
B
Bi-Met tooling:
Figure 3 shows an injection molding tool used for
making seatbelt clamps for cars. Te tool has been
manufactured using DM3D Technology's proprietary
Bi-Met tooling technology where tool steel is cladded
on a copper base using the DMD process. High
thermal conductivity of the copper base (six times
C
D
Figure 2. DMD cladding of connecting rod forging tool. (A) CAD model showing tool base and DMD coating, (B) DMD
process in action, (C) DMD deposited tool and (D) fnish machined tool.
A
B
that of steels) allows faster heat transfer, leading to
a 40-percent reduction in cycle time, while the steel
clad on the molding surface provides the required
strength and wear resistance of the tool.
Conclusions
Figure 3. (A) Steel-cladded copper tool for car seat belt
and (B) cross section microstructure of steel cladding
on copper alloy with an intermediate bufer layer.
forging process without chipping of the coating
material. DMD-built hardfacing material was about
6-mm thick to sustain severe forging pressure and
also allow for remachining of the tool multiple times.
DMD-applied tools had four times longer life over
conventional tooling and resulted in signifcant cost
savings while reducing downtime.
16 — AM Supplement
DMD technology ofers fully dense, metallurgically
bonded, protective coatings on parts with complex
geometries. Its ability to deliver multiple materials
allows it to create graded cermet coatings and/or
application of diferent metals in diferent places.
Application of the technology can produce signifcant cost savings through improved performance and
productivity.
For more information about additive technologies,
contact Tim Shinbara, Technical Director, AMT–Te
Association for Manufacturing Technology, at
tshinbara@AMTonline.org or 703-827-5243.