The Corroding Brackets Matter

Paints offer both protection and, in some cases, an aesthetically pleasing surface. Paints work because they adhere well to the surface onto which they are applied, do not crack or fade and, slow down or prevent the ingress of chemicals. But what happens when the paint starts to fail and where does the liability rest? 

Determining how and why a paint failed can be a complex matter as it involves the examination of various factors such as the right paint in terms of both the surface onto which the paint is being applied, the correct application and the correct paint for the conditions to which it will be exposed.

Recently, the laboratory was contacted by a firm of wholesale hardware distributors, who had received a delivery of 20,000 ‘T’ brackets which are commonly used to reinforce the ''T'' junction in post to beam and column to beam connections in timber structures.

What was the problem?

The hardware distributor informed the lab that in advance of placing a large order, he had received samples of brackets which he told us were made from zinc coated mild steel.

The problem, the hardware distributor had received ‘T’ brackets which were black in colour and ‘appeared to be rusting. Three brackets (photographed) were sent to the laboratory and the investigation of this matter commenced.

Using FT-IR analysis, we quickly determined that the black coating on the brackets was indeed painted with a quick, air-drying alkyd paint.

Using Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), we performed analysis on the surface of one area of interest.

What did we do?

We performed targeted analysis on within the area of examination, the analysis showing that there was no evidence of a zinc coating, therefore the ‘T’ brackets were not galvanized. The high levels of both iron and oxygen within the area showing corrosion, showed that the steel was corroding.

Our laboratory determined that the brackets were mild steel which had been painted with an alkyd paint which in our opinion had been applied to a surface which was already corroding. The bottom line, the hardware distributor ordered one thing and received something different.

We could prove this through detailed analysis. Take the unknown out of materials and paint failure. Contact us today, and allow our experts work for you.