In October 2016, we announced the Hybrid-LTW® method as a type of welding method, particularly for large-size parts. |
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This method had already been developed almost at the same time as the development
of the ACW® method (absorbance control method)1) http://www.ltw.jp/contents/acw01.html announced by Orient Chemical Industries, Ltd. in 2007. As the challenges
of laser transmission welding have surfaced, now we have come to propose
this method because it meets the users’ needs. |
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This is a new method that has features of both the LTW method (laser transmission
welding) and the ACW® method (absorbance control method). |
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The Hybrid-LTW® method consists of two optically-different resin compositions: material
transmitting laser (irradiation layer or transmission layer) and material
absorbing laser (absorption layer) as shown in Figure 1. |
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- Side of material irradiated with laser
-> light transmitting composition used in the ACW® method (ACW® composition) |
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- Absorbing material
-> widely-used black standard forming material or “eBIND® LAW®-series” that we propose |
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By using
these materials, optimization is possible. |
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[Figure 1
What is the Hybrid-LTW® method?] |
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(1) Tolerates gaps. |
In the
method to weld resin with laser, shrinkage or warping caused by forming process
produces a gap at the bonding portion, causing a welding defect. |
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In this method, as a light-transmitting composition (ACW® composition) is used on the laser irradiation side, laser light heats
the inside of the resin, penetrates deeper while melting the resin, and
expands. |
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In an ordinary laser transmission method, the welding strength lowers when
a 0.05-mm gap is present, and even when the gap is 0.1 mm, welding is impossible.
However, when using the Hybrid-LTW® even when a gap of 0.05 mm was present, a welding strength equivalent
to that obtained by ordinary laser transmission welding with no gap could
be obtained successfully. |
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(2) Optimum for welding of large-size parts |
As the Hybrid-LTW® method tolerates gaps, it is advantageous for welding large-size parts
and parts with low surface accuracies. |
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(3) Energy-saving and shortened tact time |
Unlike welding between light-transmitting compositions (ACW® composition), this method utilizes a light-transmitting composition in
the irradiation layer only to increase the heat conduction and calorific
value of the light absorbing composition. As a result, lower energy consumption
and shorter tact time compared to ACW® method can be achieved. |
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(4) High welding strength |
In this
method, as a light-transmitting material is used as the material to be
irradiated by laser, laser light heats the inside of the resin, penetrates
deeper while melting the resin, and expands. |
With the Hybrid-LTW® method, in which a large molten pool is formed due to the above process,
it is possible to obtain a higher welding strength (tension shear strength)
than in an ordinary laser transmission method. |
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(5) Acquisition of patent for the
Hybrid-LTW® method |
Orient Chemical Industries, Ltd. has acquired the patent right concerning
the Hybrid-LTW® method. To effectively use the patent right, we are proactively conducting
licensing activities. |
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