Why Ceramic Shards Break Glass

The impact of the shard against the glass creates a tiny structural failing which rapidly spreads the tension through the rest of the screen causing it to break.

Why ceramic shards break glass. Spark plugs are made of aluminum oxide ceramic which is exceptionally hard. Keep in mind that each time you heat glass the glass expands and could eventually cause the glass to break at some point way in the future. Once the crack gets started it quickly spreads ceramic stones can easily be concealed by thieves. When thrown with moderate speed at a side window a sharp shard of the exceptionally hard aluminium oxide ceramic used in spark plugs focuses the impact energy into a small enough area without blunting to initiate cracking releasing the internal energy and shattering the glass.

Although effective spark plug fragments will not work all the time. You can find beach pottery and shards on the same kinds of beaches where sea glass is found. The ceramic used in spark plugs is extremely hard compared to your typical rock. In addition the corners are very sharp.

This concentrates the force of the hit to a small enough area on the glass that it can scratch and fracture it. Mike shows how porcelain from a spark plug can break glass with ease. The stove is made to withstand this type of heat and the glass is ceramic which allows the glass to withstand that temperature without shattering. Dumps are the best sites for finding beach pottery ceramics and shards like the old tepco ceramic factory dump.

The hard ceramic fragments of broken spark plugs are great at breaking tempered glass.