impact resistance of thin glass on structural backing layer

[damienmorton]

I am building a device comprised of a 0.5mm-1mm thin glass layer bonded to a rigid structural backing layer, and this device is required to be impact resistant.

The impact resistance test for the glass is the ball-drop test, and I am wondering if there is a way of estimating what adhesive properties would maximise the impact resistance in this relatively low-velocity environment (<100m/s and <100g impactors).

For example, would a thicker softer layer act as an energy absorbing layer, or would it merely facilitate local deformation and failure of the glass.

 

[unclesyd]

You need to investigate how window films work in respect to impact resistance for glass. Early on in the development of several different types of glass films I witnessed the results of impact test using projectiles and 2x4's on glass panels and the results were very convincing for everyone, they worked.
You don't have the exact conditions presented by a free standing pane of glass, but it might be of benefit to have a uniform layer of adhesive between the glass and it's backup. As you haven't given any information about the required physical or environmental conditions it is impossible to even pretend to recommend an adhesive.
I would look for an acceptable adhesive in film form for a uniform application
Another possibility would be to use an intermediate plastic layer along with the glass. If possible, I would look at using a glass with high impact properties, like ballistics glass.

 

[damienmorton]

Window films generally go on the front face of the glass. In my case the goal of the glass is to provide a scratch-proof surface, and any plastic film on the front face will negate that.

The glass I am using is a chemically hardened borosilicate or aluminosilicate glass, and the backing material is titanium.

The purpose of the adhesive is 3-fold, firstly to attach the glass to the structural backing material, secondly to ensure that pieces of glass dont fly off when the glass breaks, and thirdly to possibly act as an energy absorbing layer.

As for the environment, it will be a marine environment, and the water absorption of the adhesive will need to be as low as absolutely possible.

 

[unclesyd]

Window films go on either side of the glass depending on their function. All my windows have the film on the inside. I am using it for heat rejection and help in the heat retention. I pretty sure if you contact some of the manufacturers so will get some adviceon on ways and means to achieve you goals.

For silicone adhesives I would use Nusil and for others Masterbond.

http://www.nusil.com/index.aspx

For some quit and dirty testing you might visit your local marine supply store and look at thier line of underwater sealants and adhesives.