One of the main advantages of clinching is its ability to join dissimilar materials and combinations of different material thickness. Although generally very tolerant, the process works best if the points below are observed.
The material thicknesses quoted in the table are only approximate and will be affected by factors such as material strength. Application-specific values should always be determined by trials.
| Factor | Guidance |
|---|
| Minimum thickness of material |
0.5mm
The material may become too thin or tear if it is less than 0.5mm thick. Also, excessive clinching forces may be required for the punch diameter used and this could cause damaged tooling.
|
| Maximum thickness of material |
3.0mm
Thicker material may require forces in excess of the punch capacity.
|
| Maximum total thickness of joint |
6.0mm |
| Maximum ratio of thick to thin when clinching a combination of two different thicknesses |
Approximately 3:1
The ratio is affected by the material type and its properties.
|
| Material on punch side when joining materials of dissimilar type or thickness |
The thicker, harder or stronger sheet should be placed on the punch side. |
| Maximum thickness of organic coating |
25µm
Thicker coatings may cause reduced joint strength due to insufficient interlock of the metals. Coatings with insufficient ductility may crack and flake although warming the material may help to overcome this problem. There is a risk of tooling contamination which may lead to variations in joint quality.
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